Interesting... I use my bike for exercise mostly, so pushing hard and going fast (for my conditioning and bike, not as fast as others!) is what I do. I found discs (mc) to be a lot "surer" AND had a scary experience on a bike when I got hit with a rain shower before I got back home. All of which makes me feel they WOULD be better!

I'm sure I could retrofit, BUT my first priority is ditching these "twist" shifters I detest!

BTW, I also DO have issues shifting my chainrings... but just upshifting (to next size up). I "learned" from the owner of this new bike shop I went to (a block from me!) that granny & middle ones have a kind of "dimple" on the inside that is needed to "help" the derailleur get the chain up to the next gear... mine are pretty worn and he said I need to consider new ones soon. I have a good old USA made steel frame so re-doing the whole drive train I think IS in my future... more so than disc brakes much as I'd like to have them!