Not saying it's proven -- but there's nothing terribly ideological about it either.

Kind of like listening to bad music (or pretty much any kind of music over and over again) can stunt your musical development... or eating too much junk food can leave you with a taste for more and more of the same... it wouldn't surprise me that too much bad porn leaves some people with bad, or just immature sexual tastes.

And to the production of... lots and lots and lots of bad, nasty and just shockingly dull commercial porn.