I believe the problem is that many directors don't actually use real lesbians. The girls have no problem being seen together, posing, etc but lesbian sex just really does nothing for them so they fake whatever real contact there is and use the dildo to avoid doing things like actually eating pussy or kissing.
Often, what little pussy eating there is consists of one girl wagging her tongue as close as she can get to the other girl's snatch without actually touching it.
It seems they often hire these girls based solely upon how attractive they are and not whether or not they actually like women. In order to have any real heat with a lesbian scene, you almost have to have real lesbians or it just ain't gonna happen. You'll get 20 minutes of tongue wagging and closed mouth kissing (if you get any at all), lots of dildos and if you're lucky, a few seconds of actual contact here and there.
It's gotten to the point to where if I'm looking for a good lesbian flick, if I see one dildo on the box cover, I usually drop that one from consideration (unless I'm familiar with the people involved and know they'll put on a good show). If you don't actually see a face buried DEEP in a pussy on the cover, you're probably not getting real lesbian action (and even then, it's hit or miss).
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