Well if you can learn some lessons then even bad experiences can end up good in the end!

I was thinking about the "use the big ring when riding downhill" advice. In most of the places I ride, the downhills are followed by short bridges over small creeks which in turn are followed by big uphills. So if I shifted to the big ring going downhill I would have even more downshifting to do at the bottom than is already necessary. But then between the finicky right knee and the asthma, I probably ride up most hills in easier gears than many of my riding buddies.