Thanks for all the great suggestions so far, and some great stories.

I like the idea of kinda giving suggestions and pointers through the repair, or asking the rider if I should do it for them.

I wasn't in a rush or anything, I had just started my lesuirely ride home from work, and happened upon a rider in distress a few minutes into the ride. if this happened on the way TO work, I probably wouldn't have stopped.

The guy seemed like he knew how to change a tube, he was just a novice, and did a few things differently than what I would have done. Used 3 levers to take the tire off, where I could have used only one, and botched the patch attempts..

Part of the slowup was because my pump was in schrader mode, and he had a presta tube, and I had to change it over, having never done it before.

I asked him if he needed help; it wasn't like he flagged me down or anything.

Thanks all for the advice, and I will use these suggestions next time. I think the 'teaching' method will be the best route next time if I encounter a novice tube-changer/ tire patcher.

I really felt like doing something nice yesterday, to make up for the rest of the time for being a jerk and a *******.