I can't imagine Simon was that thrilled carrying the cross that day. More likely, he cursed his rotten luck and probably said more than a few choice words under his breath to God that day.
But if he was even a little bit open to it, I wonder if he didn't take something away from the experience. If being compelled to carry another's burden even for a little while didn't shape him in some quietly profound.
We'll never know, of course, but I wonder. Because the heart of compulsion is losing control. And when we give up control -- amazing things can happen.