Needless to say, I've found that cleanliness of the drive train is paramount to good shifting performance. I'm a bit obsessive, but my riding benefits significantly from it.
No doubt. And I agree. It hasn't been an issue yet with the new bike (and hence new drive train), but especially when I was on a small frame with multiple rings up front - getting it tuned to shift all the way through was a bear, and then almost any ride would knock it out or grunge it up enough to cause trouble.
It would be better yet if I would stop the bad habit of shifting under load ... mostly I'm well behaved, but when I'm not, it's so loud. I can just feel the system straining.
Apparently, mud got into my brake calipers and was causing drag on my disk -> wheel. Not sure if that was during the ride or got knocked in when I started hosing. I think I got it all out.
Hey, how is your bike after fall? Is everything in working order?