Does he take any sort of stimulants? I take them and have found it harder to reach climax in certain positions, particularly if I am not tensing my thighs. However I found a fix for myself was to enjoy the sensation of my ex-girlfriend having sex with me but for the most part it's thought. I let my imagination run wild slid my hands all over her body enjoying every curve and muscle constricting and contracting in pleasure. The hardest position I'm having cumming right now is the squatting position as if sitting on a low toilet. He really needs to let his imagination run wild. Also I found lots of foreplay for the other person tends to make it easier for me and it could work for him. He riles you up and listens to your moans feels your body quiver and shudder in pleasure and seeing you enjoy yourself so much from what he is doing is a huge turn on not to mention ego boost for him and he'll be able to relax. If he isn't relaxing he is essentially just forcing himself to cum. When he gets really good at it he can go for hours and finish any time he pleases. My ex girlfriend loved and probably still would if we didn't have disagreements about how we'd raise our future children. She was a free spirit and I a forever student, always wanting to learn I loved information and scientific advancement she loved nature and doing everything impulsively. Honestly I miss her but she could of brought the problems to my attention and we could work on them like you are working on them with your boyfriend. But then again I like logic and she doesn't think logically but emotionally. It's all about frame of mind for your boyfriend and if he can get out of his head for a while he will be able to cum in any position.