I used to replace the tube with a spare if it happened on a ride and then patch the original when I got home and that becomes my spare. But lately I've been rethinking that. Since moving to Boston area from Vermont, I've found that the patch rubber degrades quickly (much more quickly than inner tube rubber, probably because it's meant to be soft and sticky). I think it's the same thing in the air that makes the people here horrible drivers. But patches don't degrade when they're inside a tire, for whatever reason.
The solution is that I patch tubes while I'm out riding unless the weather is horrible or I'm in a huge hurry. That way the patches stay inside the tire and they're fine, and my replacement tube stays patch-free. Bonus, it stays tightly rolled up and I don't have to spend time squeezing the air out to get it to pack down small.
Last edited by scarlson; 07-23-19 at 09:15 PM.