It is possible to look at the traffic coming from two different directions, and make a judgement call on that. He was no spring chicken, and would have used his experience to judge whether he could make the gap without causing significant risk to others.
The risk is that you are transposiing the limitations in your judgmental and riding skills into his situation. You may have considered it too dangerous as you couldn't process the info and act on it, but there is nothet into say that others couldn't.
the fact that the only thing which stopped him was the sarcasm from the OP is an indicator that he ha a bit of spare capacity in his ability to act on the info as it presented..........
I think the term I'm looking for is 'experience'