Pretend you are him and write down exactly how you think he would recall the event. Approach him and explain that you would like to progress your own flying and whatever happened in the cockpit obviously made him uncomfortable and you would appreciate it if he told you exactly what it was that made that happen. See if he tells you anything useful about yourself and see how it compares to what you wrote down.
It's likely that whatever you were trying to point out was a useful and valid point. But if the person you are trying to impart some knowledge to is unwilling or unable to take it on board then forget it (unless you need to safeguard the aircraft in which case take over). Thing is, you may well learn something about yourself that helps you deal with a situation like that in a more effective way in the future. Not suggesting for a moment that you did anything wrong, far from it, but friction in the cockpit is never good and just because other bloke isn't interested in learning about himself and his craft doesn't meant you shouldn't.