I actually can say I can feel my fiance tighten up when she climaxes. But there are some occasions when she is really wet that its to intense or lubricated to feel her. I sapose it would change with person to person and the situation at hand.
Oops - you asked if they could feel, not tell.
Ignore that last answer ;)
DH says he can sometimes.
Unless you are like me, and have "afterglow"
No hiding or faking here - if I have an orgasm, everyone in visual range will know ;)
Based on what men have told me... no.
That's why they usually ask me how many I've had, if any.