When I'm on mnk the only times I don't go for positionals is when i can't ( leviathan, demon wall) or when it would mess up stacking (twintania snakes, titan ex) On my tanks I try to avoid spinning mobs, but sometimes I'll run a semi circle around a large pull to spread the overpower/flash love. Oh and those buffs like ht dk. I see no reason not to keep them up.