If we are talking Workshop Prison in general, then I´m more in line with JP and Toad, though I don´t agree with the stats. No point in arguing about that, though

Are we talking against Monobrown Mud or against Workshop Prison in general?

The Mud player can rarely prevent the Tog player from playing anything at all. But the Mud player CAN prevent the Tog player from playing more than one spell a turn (maximum) and thus reduce the Tog´s deadliness, should it ever hit the board.  

Trinisphere in itself doesn´t prevent Tog from hitting the board but it does prevent it from being its usual, deadly self.

First-turn Tog does not happen that often after all. And this is assuming that the Tog player goes first. If he doesn´t, he is not going to play a first turn Tog barring a hand with Force of Will

True, the game plan is to drop a Tog as quickly as possible. And that is just what I find is quite difficult to do against the Mud players, that I usually face.
Between Trinispheres, Spheres of Resistance, Chalice of the Voids, Smokestacks, Tangle Wires, Wastelands, and Strip Mine I find it very difficult to maintain the mana to play the Tog. It requires a really quick start (preferable going first).

Notice that the deck in question is the Mud deck with multiple spheres af the various kind (I assume it includes chalices too in the lack of a decklist). I find this much harder to beat than say, $T4KS.

I don´t think the Tog deck is overrated at all. I´ve managed quite good results with it so far. (split a Mox Pearl in the finals once).

I believe, that your experiences with Tog is a result of the fact, that you play one of the absolute most horrible decks a Tog player can face. A Mud deck with multiple Spheres (Trini & Resistance) plus Chalices is just devastating for the Tog player. Tog´s fighting chance increases after sideboard but is still not very good. The possibility of the Mud player taking home either game two or three is just too great. And the Mud player usually wins game one.  

/Rasmus