Is he a cheat?

Question…is it true that a guy climaxes faster when he hasn’t had any in a while? I ask this question b/c a friend of mind had the following situation. Her and her guy hadn’t had sex in months (about 5) for a number of reasons. When they finally did have relations again she said it was great and long lasting. He tried out new tricks and everything. She felt that this was a sign that he had been with someone else during their hiatus. Now, I know plenty of guys claim that when they haven’t had any in a while the first time they get some they can release pretty quickly, but is this really true? Also does showing off new tricks indicate cheating? Just b/c they haven't had sex in months and when they finally did he was good with stamina doesn't mean he's a cheat right? Unfortunately, I can’t give this particular friend advice b/c I already think her man is cheating and probably has been for a while (but not for the reasons mentioned above). So since I can’t be objective I’ve decided to open it up for discussion. Should she be worried he’s been getting his loving elsewhere? Is it normal for a guy to climax quickly after they’ve been inactive for a while?