I dunno, the idea of "hold the MB b.3 to punish" looks nice on paper, but why would I wake-up at all if you're just going to sit in my face with a Mb b.3 on hold? Against Catwoman we have to be careful because of the cross-dash thing so I feel like Mb f.3 would be the better option since its double hit, has a lot more active frames, and hits overhead meaning if Bane is sitting there blocking low to avoid the dash set-up he gets opened up, where as if you did the Mb b.3 he would end up blocking it regardless.
Just my thoughts on it.
The idea is you're only MB the b+3 if you see him do wake up command grab. Otherwise you're not using meter, you're staying safe, and you have a chance to blow him up. Cross up MB Cat Dash mixed up with f+3 is good and what I do often but it's risky.