Ummmmm
Your title was exactly what I was thinking when I read your post…
You’re asking so many random half-questions, that I don’t know where to start, but honestly most of this stuff is being discussed in threads right next to this one. =P
Well, P/D isn’t really that usable. If anything, it’s only usable because it’s not unusable- i.e. weaponsets like S/D are unusable because they have only two decent skills, one of which has almost been nerfed into oblivion anyways. Either way, P/D builds have always kinda sucked IMO (at least, compared to other options), but right now it’s looking to be a better weaponset than most of the others.
D/D (as well as D/P) are still both viable sets, but with the amount of conditions in the current meta and the fact that dagger has no cleaving ability (meaning that you’re going purely single-target in a meta where AoE wins), Dagger builds have been suffering recently.
As for SB… I mean, it’s still usable… It’s just that SB has always been more of a utility weapon than anything else; it’s a filler for when you’re at range or have run out of initiative.
Anyways, as a result, I’d stay away from devoting too much time/money into thief, and I especially wouldn’t suggest getting a legendary for thief right now. Hopefully we’ll be able to ride out the storm.