Yes, that's how I do it in LR. I suspect that the Adjustment Brush isn't being used to it's full effect.
The ability to duplicate an existing brush in LR5 is quite useful; at times, the BG isn't quite black enough, but doubling it works well.
However, I concur with Dan's comment - it isn't quite up to level of PS.
I only wish that LR would incorporate the HSL Panel into the Brush too, not just the main screen.
Glenn