Percolation? Heat soak? Don't drive during summer??

Ok, so I'm reading that you had somebody crank it over while you held the coil wire and it fired normal while it was hot and wouldn't start. Then did you check the spark coming out of the distributor the same by pulling a plug wire and putting a spark plug in it, while it's hot and won't start?

I havent tried with a wire and plug, but I can try it out.