My experience of having shagged a contortionist (gymnast actually, but for these purposes the same) is that she was so into showing off bendy shit that the focus wasn't on sex. Seeing a vagina at a new angle is entertaining for roughly one second, then sex in an awkward position is entertaining for about a minute. Then you just want to bang, but she is still trying show off moves. I'm horny, got a covered boner. Penis in vagnia, out of vagina, repeat, is my objective. Observing the angles of her legs or spine at the expense of my sausage not getting wet is just annoying.