I've just completed naga city with a TT goblin paladin. It's a nice strategy.
I'm really interested in hearing about this in more detail. It took people ages to wrap their heads around the idea that TT is really, really powerfull at all stages of the game. And it took ME a long time to even think about locking myself in TT with monoteism (for me it was the potion change that did it, as well as all the extra gold that allows for more conversion fodder, and that was before the minimalist profile).
And on topic - I've cleaned out everything in shifting passages with a goblin assasin (with only gg and TT), on the sloppiest most reckless run ever. I barely ayed attention to what I was doing, and I expected to fail myself into a dead end at any point - I pulled through anyway. But then, I was successfully using goblin assasins in vicious dungeons before, they were great wherever you had animated armors, illusions, zombies or any other assortment of fat bastards pilling up in one place.