Yep, you can't just stay and hit, hehe. It may not be the better dpser or anything, but it's a hella fun class to play (except when you're lagged >.<), give it a try! I still haven't seen many thieves around, except... WvW. Lately I've been exploring these maps and leveling there and I've learnt to hate thieves. Sometimes five thieves just stay in the middle of the map, waiting to ambush people leaving the garrison.