The difference between playing this as control and combo-control comes down to one card choice and the role you chose to play. I'll be happy to demonstrate this on MWS using the mirror match. (One plays Confidant, the other Cutpurse).
I call you out on that mirror match.
*sigh*
Dozer^: alright, finished
Dozer^: Klep, you may have to demote me
Anusien: You don't get demoted
Anusien: You DO however get ridiculed for validating AmbivalentDuck's existence
Basically, that's all the story right there. Confidant (him) won vs Cutpurse (me) 5-1 games, with both playing the following identical list that Kasuras was kind enough to PM to me:
4 Polluted Delta
3 Underground Sea
3 Wasteland
1 Swamp
5 Island
1 Strip Mine
1 Black Lotus
1 Mox Emerald
1 Mox Ruby
1 Mox Sapphire
1 Mox Jet
1 Mox Pearl
4 Dimir Cutpurse/ Dark Confidant
1 Circu, Dimir Lobotomist
1 Darksteel Colossus
1 Ancestral Recall
1 Mystical Tutor
1 Vampiric Tutor
1 Imperial Seal
1 Demonic Tutor
1 Cunning Wish
1 Fact or Fiction
1 Skeletal Scrying
4 Impulse
4 Mana Leak
4 Force of Will
4 Mana Drain
4 Brainstorm
1 Time Walk
1 Yawgmoth's Will
1 Tinker
// Sideboard:
SB: 1 Skeletal Scrying
SB: 1 Crucible of Worlds
SB: 1 Psychatog
SB: 3 Energy Flux
SB: 3 Engineered Explosives
SB: 1 Claws of Gix
SB: 1 Coffin Purge
SB: 1 Counterspell
SB: 1 Echoing Truth
SB: 2 Darkblast
Confidant or Cutpurse were in every opening hand, that's what we agreed on since the point was to compare Cutpurse and Confidant. I don't think the actual game logs interest anyone (though I have them on request), so I will give a summary of the six games here and then tell you what I learned and which lessons we can draw out of this, if any. (I am on the play for the first three games, AmbivalentDuck for the other three.)
Game 1: I have a Wasteland, Jet opening, he answers with Swamp, Pearl, Confidant. I could have Forced but didn't, which in hindsight is obviously wrong because I don't have a blue source and fail to draw one next turn either. He later gets a Darkblast with Cunning Wish while I have Cutpurse which attacks into Confidant and both die. He plays another Confidant and Impulses and Brainstorms, while I FoW his Ancestral and he Leaks my Fact. After he has Wasteland and Strip Mine, I topdeck Tinker on an empty hand which I obviously do not resolve and Confidant kills me (instead of him, heh).
Game 2: I start off with Island, Ducky goes "Island, Sapphire". I Force the Sapphire and he Mysticals for Ancest. He doesn't get a land for the next couple of turns and I build up lands with multiple Leak backup -- looks good. He gets some lands, and at the end of my turn (#11, for those who care), this happens:
0:06:58 [AD] AD sacrifices Polluted Delta
0:07:18 [Dozer] Dozer plays Mystical Tutor from Hand (getting Force of Will)
0:07:22 [AD] <AD> Ok
0:07:26 [AD] AD puts Underground Sea into play from Library
0:07:54 [AD] AD plays Vampiric Tutor from Hand
0:08:23 [Dozer] Dozer plays Brainstorm from Hand
0:08:40 [AD] AD plays Ancestral Recall from Hand
0:08:43 [Dozer] Dozer taps Polluted Delta (getting Island)
0:08:43 [Dozer] Dozer taps Polluted Delta (getting Island)
0:09:05 [Dozer] Dozer plays Mana Leak from Hand
Leak resolves, countering Ancestral.
I resolve Brainstorm, Ducky resolves Vampiric Tutor.
The crucial thing here is that I had to shuffle away the Force I tutored for to Leak the Ancestral, and Ducky gets to untap. He plays Confidant, passes and I play Cutpurse. They trade, and though I can Impulse and Imperial Seal for Ancestral, Ducky Forces through a Scrying for three and Imperial Seals up a Tinker I can't stop. I Ancestral next turn into Lotus and FoF. Neither that nor Impulse and a Brainstorm gets me the Cunning Wish that would fetch Echoing Truth, and DSC kills me. Big frowns. I must have made mistakes in this game, but I can't identify them.
Game 3: I mulligan down to five, one of which is (as in the terms of the games) a Cutpurse. I make a Polluted Delta and say go, and Ducky has Delta, Pearl, Confidant. He continues with Time Walk, Impulse, Vampiric, Ancestral which I try to Drain in vain. He then has
triple Brainstorm + shuffle effect in a row, the last of which is a shuffle brought on by Tinker. That's all she wrote.
Game 4 (from here on, Ducky is on the play): He starts with Island, while I have Delta, Pearl. His Swamp yields a Confidant, while I Vampiric for a card I can't remember. While he has Confidant going, I run three Cutpurses in a row into counterspells, and he reveals Will and Time Walk with the Confidant. I can play Demonic for Tinker and Drain his FoF, so I should be in a good position. He Walks which I Force (don't want him to draw two extra cards vs my Tinker), and he plays Demonic Tutor I can't stop (with Will in hand). On my turn, I topdeck Strip Mine for his USea (this was important for keeping him off Will + Walk mana) and play Tinker for DSC.
At this point, I am at 7 life and Ducky is at 11, so Colossus is lethal but Ducky has Will in hand. He does: reveal Fetch with Confidant (no damage), Brainstorm, crack Fetchland, play Sapphire, Will, Walk, Brainstorm. Next turn sees him revealing a Wasteland (no damage), Mystical Tutor for Cunning Wish, Brainstorm, play Cunning Wish for Echoing Truth, returning DSC to my hand. A lot had to come together for that Wish to happen... anyway, I lose.
Game 5: I draw a hand with 3x Cutpurse, 1x Circu, Sapphire, Emerald, Island. If this hand had just a single black mana, it would be very good. Alas, it doesn't! So I mulligan two times, but Ducky lets me draw up to seven again.
We open with just Island, but on my EOT Ducky Ancestrals which I Force, and of course he has the FoW to push it through. His next turn lets Confidant come into play, while all I have is an Imulse. He reveals Skeletal Scrying with Confidant, while I get another Impulse which he answers with a Brainstorm. In my EOT, he Scryings for four which I can Drain, but he untaps, reveals Brainstorm with Confidant and plays an upkeep Mystical for Tinker
without a Mox in play. I the play Cutpurse and Impulse with my Drain mana. He Impulses
and Brainstorms EOT.
At this point, I hold Force, Cutpurse and Leak as my three cards. I know he has Tinker in hand. He reveals Wasteland with Confidant and plays Mox Ruby. I Leak that, because if he pays he has not enough mana to Tinker. He lets Leak resolve, puts the Ruby into his graveyard, plays Mox Jet and Tinker. I Force, he Drains and with the five Drain mana, he plays Will in his second mainphase.
The correct play would have been to let Ruby resolve and just fight over the Tinker, but I didn't put him on the second Mox. With Will and Drain in his hand, though, neither play could have prevented the Colossus that subsequently beat me after playing Cunnning Wish for Echoing Truth, bouncing my two Cutpurses.
Game 6: I am pissed off. No, seriously, I am! Especially after reading the logs again. Can it be that I am in fact losing to the guy who advocated leaving out Ancestral from a deck he claimed to have playtested? And why is it that I don't get any brokenness, or triple Brainstorm-shuffle-combinations, or any of the singletons Will, Lotus, Cunning Wish or even Circu?
This game, we both mulligan to six. And finally, finally! I get Ancestral in my hand. I am determined to not lose 0-6 even though at this point, I have accepted that I made several mistakes and Confidant is more than annoying when unanswered, and my answers are 4 Cutpurse, 1 Circu and a Cunning Wish I never drew even once. Not very reliable!
Ducky opens with Delta, I open with Delta, Emerald and directly Ancestral, to which he responds with Brainstorm ("wasting" a Fetchland shuffle) but has to let it go unanswered. I FoW his Confidant and keep Leak in hand. On my second turn, I play Brainstorm, draw Lotus and Tinker off it, crack Lotus for BBB, tap Emerald for 1, tap the Sea for blue and play Tinker for Colossus followed by Vampiric Tutor for Force of Will with double Leak in hand and tapped out.
Ducky shows me his hand: Dark Confidant, Yawgmoth's Will, Skeletal Scrying, Imperial Seal. He can either go for Will, Brainstorm or Seal, Scrying to get a Cunning Wish. He decides for the Seal + Scrying way, but it's moot anyway because I draw FoW next turn and he cannot beat double backup. I take a game! The only one. Not really satisfying...
Conclusion: First, some tidbits from our after-game conversation.
<Dozer> I still claim that Confidant doesn't belong in the deck, though
<AD> I agree.
<AD> Darkblast kills it.
<AD> I'm just saying it's better than cutpurse.
<AD> If creature removal dies down, I'd put it back in.
<AD> Fog would playable as a 1B cantrip.
<Dozer> Cutpurse is better against Gifts etc, though
<AD> *nod*
<AD> Having that Mana Leak/Drain up turn 2 is huge.
<AD> I'd actually say that Cutpurse would be bad in the control mirror.
<AD> Let me sub in 4 morphling for Confidant
<AD> Actually, 4 tog
<AD> Seriously, tapping out turn 2-3 is bad.
<Dozer> kinda, yeah
<Dozer> well, I'd have to play against both versions with Gifts
Looking back, playing the games the way we did was not effective. Valid conlusions about the versatility of Cutpurse vs Confidant in the control matchup can't be drawn from this. I must admit that the card advantage from Confidant probably was deciding in the games, because he cantrips vs my Cutpurse while I get nothing from the three-drop which is then wasted energy. On the other hand, looking back it feels like both creatures actually were irrelevant because their effects were overshadowed by brokenness. Feel free to draw your own conclusions, though, maybe I'm just trying to draw a veil over the affair!

I still think an active Cutpurse is better against an opponent without blockers, though, in this deck. I have been on the receiving end of Cutpurses already, and it's really strangling.
However, Kasuras has told me that he dropped the creature entirely, because neither Confidant nor Cutpurse was good enough in the long run. I think that is the way to go, although I really like the Cutpurses. Other comments on the deck: Ducky advocated Chain of Vapor instead of Echoing Truth as wish target bounce, and we both felt that the Counterspell in the board really should be Misdirection, or Misdirection might even be main.
I am leaving it at that. I hope you enjoyed this little experiment. AmbivalentDuck, whose posts are not too well received, stood up to his words, and we conversed, played and parted politely. I credit it to the atmosphere of TMD that this is possible. So, thanks all.
Off to get myself horribly drunk because I lost to AmbivalentDuck, but before my writing becomes sl...sl...slurrrryy, i willll lleeaf yyouuuu wis the folovink kwotes *hic*:
[00:55] Anusien: Wait, wait. Did you apply optional rule 402.1c?
[00:55] Anusien: The one where he isn't allowed to play Ancestral Recall?
<AD> I'll let you post the results.
<AD> I seem overly skilled at creating flame-bait.
Dozer
/edit: OMG I spent my 400th post on this. Is that significant?