It's still viable if you're making an alt, to transfer over your a-grade weapon and only attack passive mobs. They won't aggro when you miss, and when you hit you will oneshot them. It gets really boring tho.
It is completely useless for nukers. Even on melees I would not try it - ok, so you can one-shot anything when you finally hit it, but what is when you get aggro mobs on you? Then you HAVE to hit them, and I would hate to miss ten times in a row when you NEED those hits...
When you twink, simply give the toon top equip of the grade he can use and good buffs, that should be enough. And it is probably even faster than singling out passive mobs and air-swinging two or three times before you finally one-hit them...
Friend of mine actually did it on his Palus Knight with a berserker sword from 28-40, it was pretty good actually and when shadow sense kicked in, he would miss a lot less. We did have guidance 3 and he could use his power strike + sting, having a god awfull accuracy doesn't affect ur skills.
We were 3 in the party, so even if he'd miss, we'd still be killing the mobs. I don't really think it's a viable option for soloing but maybe with a blunt / fist it might be doable, specially at night with shadow sense.
Oh and on a side note, ur SA don't work if u don't have the grade mastery ... so even if u get a Blunt with + accuracy u won't actually see the accuracy increase untill your level 40. (unless this changed since C4)
I tried to use a dark screamer and an akat with my alt scout when he was lvl 20. Too many misses on the bow and too may mob hits in between dagger misses. They went directly into storage.