At first I could barely tell with my boyfriend, he'd just slow down and stop and I'd be like, okay when did that happen lol. Which made it difficult when I was on top because I could never ever tell, so wouldn't want to stop if he hadn't or carry on for ages if he had. Was so irritating. But now I'm more tuned in to him I can tell by the subtle things I'd not noticed before it just took a bit of time to get tuned in x