Congrats on the win! Good to see a tutorless 5cStax put up some results. Looking forward to discussion of card choices, assuming I can find it when it goes up on the new TMD.

No problem. I spent the months playing MUD varients (and Crushing Chamber, etc ) capitolizing on Thorn and then Lodestone Golem.
When I got tired of losing games to Ancient Tomb, I decided to go back to Welders. Your 5cStax list on
www.channelfireball.com started as the baseline. I started with 3 Ancient Stirrings instead of Chalice Welder and Crop Rotation. It was fun, I split top 4 for $140 store credit.
Next time, no Ancient Stirrings as I wanted Balance Crop Rotation maindeck.
This time, I tweaked my deck for the local meta and hoped for the best.
// Lands
1 Bazaar of Baghdad
3 City of Brass
3 Gemstone Mine
4 Mishra's Workshop
1 Strip Mine
1 Tolarian Academy
3 Wasteland
1 Mishra's Factory (4)
// Creatures
1 Duplicant
4 Goblin Welder
4 Lodestone Golem
1 Sundering Titan
1 Triskelion
// Spells
3 Chalice of the Void
2 Crucible of Worlds
1 Mana Crypt
1 Sol Ring
1 Mana Vault
1 Black Lotus
1 Mox Emerald
1 Mox Jet
1 Mox Ruby
1 Mox Sapphire
3 Null Rod
3 Smokestack
4 Tangle Wire
1 Tinker
1 Trinisphere
1 Ancestral Recall
1 Mox Pearl
3 Thorn of Amethyst
1 Crop Rotation
1 Balance
// Sideboard
SB: 2 Duplicant
SB: 1 Thorn of Amethyst
SB: 1 Aven Mindcensor
SB: 1 Red Elemental Blast
SB: 2 Choke
SB: 1 Sculpting Steel
SB: 1 Diabolic Edict
SB: 1 Echoing Truth
SB: 2 Seal of Cleansing
SB: 2 Rack and Ruin
SB: 1 Suppression Field
Card Choices:
Bazaar of Baghdad. I played 1 instead of 2 because I only own one, and with Crop Rotation, I felt 1 Bazaar was enough. It's only really good with Welder out, and Welder doesn't always see play.
1 Mishra's Factory. I wanted an extra beater vs Oath of Druids/Fish/maybe Goblins. Also, with Crucible, It was a "free weld target" especially post Hurkyl's Recall if Welder was on the field.
1 Triskellion. I am always nervous playing Shops without the token Trike. Last tourney, Klemic got Painter Grindstone off at 3 life, I had Welder in play, but no Trike maindeck due to Null Rods. I had to tell myself, that I play Null Rods and moxen, and Trike at worst is a 4/4 beater.
2 Crucible: Teammate Austin tried to convince me that as the Stax Player, I have ALMOST only permanents in my deck, and I will always win the permanent war, so 3 or 4 is too many. I won't play with less than 2.
4 Tangle Wire: This is a combo with Lodestone Golem, Smokestack and Thorn of Amethyst. It's just awesome right now, and 2 is WAY too few, 3 good enough, but 4 is the awesome sauce.
1 Balance, no tutor: If I get it in hand, then my opponent won't know about it, and I can maximize its use. It's proved its value resetting the board, giving me control of the gamestate. Agains Webster in the Finals, I had it in my hand game 1 with Emerald and Pearl out as my only board presence. I sandbagged it, waiting to get better value, but I didn't do the math correctly, and Balance was rendered useless in the Oath War.
1 Crop Rotation: I rarely play this card, and am trying to give it a shot. I think I played it a few times but don't remember. It's been stellar on MWS, but that doesn't say much.
Sideboard:
2 Duplicant Hate against most decks
1 Thorn Hate vs Storm/Tez/Blue Decks. Anything but creature decks, really.
1 Aven Mindsensor Hate vs Tutor.dec and Fetch.dec. Actually, this card was overkill as I had plenty of other stuff to bring in. But the Ninja factor of it always makes me want to keep it.
1 REB Hey, if I get it, cool. I won't play their game and side in 4 of these, as they will always have more counters than me.. If I get it, great.
2 Choke: Hate vs Basic.dec. Also, I own 2 now, so it's an option. I'll likely go down to 1 in the future for same reason as REB. If I get it, great.
1 Sculpting Steel: For mirror/MUD matches and confirmed Inkwell Leviathon decks.
1 Diabolic Edit: Vs Oath and Tinker Fatties
1 Echoing Truth: Vs everything, but mostly Oath and Tinker Fatties
2 Seal of Cleansing: Vs Oath, Shops and Time Vault decks
2 Rack n Ruin: There were a lot of usual shop players there, but some chose to experiment with blue/black cards that day. Ancient Grudges might have been better, but adding Rack N Ruin was a last minute meta call.
1 Suppression Field: Sensei's Divining Top, Jace, Tezz, Fetchlands, Library at Alexandria, Voltaic Key, Time Vault, Shivan Dragon. This came up game 2 in finals vs TPS/Vault.dec. It hurt me as much as it hurt them, which means that it hurt them bad and make my Smokestack awesome (sac a useless top/Time Vault, etc) but there were other lock pieces in the puzzle.
On sideboarding, we all have to revise our strategies every time G2 or G3 happens. My deck is geared to hate out the Blue Decks, but Oath decks have so many different ways of winning, that they can often get there by countering my first two threats, then play something broken.
On a particular matchup, I decide what cards in the sideboard are good, and then look at the maindeck and find out what cards are not as good (like 2nd Crucible, Mana Crypt, Trike, Crop Rotation, 4th Welder, 4th Golem, maybe a Smokestack etc) and then only side in cards that can replace cards that are not as good. So if I have 6 cards I am willing to side out, that means on 6 of 10 SB cards can make it in. If I am on the draw, then I can side out say 2 Chalices, for 2 more better cards..
That's it for now (gots to go to work).