I would HIGHLY disagree with that. A black faced Bassman head into a 2 x 12 cabinet makes a fantastic amp setup for classic rock, etc. No...metal heads wouldn't go for it, but crank that puppy up for some natural "grit", and it is really nice.
I guess you have never plugged into a twin and had it on 10 and still sparkly clean, eh?? just kidding of course, but I would consider that amp much less flexible than a bassman combo, albeit, a twin is a fantastic amp too.