I just got my 1st flat in 9-months and 12,000-miles yesterday... Two shards of glass was embedded in the rear tyre. Probably took a couple miles to work themselves through the kevlar belt, then the Mr.Tuffy and finally the thorn-resistant tube with Slime. I guess I'll get some of those tyre-scrapers that the touring guys use...

Yeah, I just throw a new tube in and deal with patching the tube later.