I don't think people say "piss break" when the Divas are on because they think Divas matches are inherently pointless. I think they just recognize filler when they see it, and we're used to seeing Divas used for filler a lot. Even AJ's mega title reign had patches where I remember nothing at all, and sometimes Lita and Trish were just valets even at the peaks (Trish and Lita did help get Christian and Edge, respectively, a good deal more heat though).
I get wrestling needs to have structure and some people just have certain roles. But I also hate leaving a stone unturned if something may be there. If the writers readily assume the audience doesn't want adequately booked feuds between the Divas then we probably won't get any. That's a low ceiling being set when there's evidence to show that not only are there plenty of Divas, now and in the past, with enough talent to be used for more than that, there's also plenty of fans interested in the Divas.
Isn't Total Divas one of WWE's most successful side projects? I may be wrong but isn't there also a growing female audience, especially considering WWE's contribution to women's charities?
I disagree that Kharma was necessarily going to end up the female Khali and I think WWE took Beth Phoenix for granted. We're obviously different and it's your right to not care about whoever you want. I won't argue and try to convince you they're great or anything, but...
Why didn't WWE ever book Beth Phoenix vs Natalya? A few years ago when the top girls where Melina, Maryse, LayCool and whoever (btw remember LAYCOOL!?) Beth vs Nattie was probably the one potential clash that made a segment of fans (well, ones I heard on the web) think "Hmm, now THAT would be interesting". There's a ready-made rivalry that just didn't happen, why the hell not? Did the writers just assume before trying that nobody would want to watch it except the pervs?