Oh I can tell, at least I can now. Most of the time. He definately gets just a tiny bit harder right before he cums. I know it well from blow jobs...it's just the right point for me to back off a bit to drag out the fun. I didn't realize at first that it was what I was feeling inside as well, I just knew that even if I'd just had an orgasm myself...everything would go from "oh my god he feels good" to "OH MY GOD YES!!" just a handful of strokes before he came. Even if he wasn't moaning, grabbing my hips, saying wonderful things.....I'd know because his dick rubs me differently just then. More firmly, I guess.

I have to admit, my sensitivity to it depends on position sometimes, and, errr, exhaustion I think . It's something I pay a great deal of attention to when I'm on top....when I feel it I know to stop dead and wait for him to relax. But after I've cum a couple of times...I don't know if it's lubrication or just wearing out the sensors, but then it's not as easy to tell. Of course, if he's not in the mood to be patient with my teasing, he's learned to try to sneak his explosions into the midst of my orgasms....when I couldn't stop moving on him for anything. Sneaky...but much fun .