As mentioned, no one is going very fast when fixing a flat. I lived for years in the southwest desert, where goatheads are ubiquitous, and the only way to ride was with thorn resistant tubes and tire sealant. With that system in those conditions, tires needed to be topped off about once a week. In those conditions, with normal tire/tube combinations, a ten mile ride could mean patching eight punctures (words of experience). These days, with a cargo bike and bolt on hubs (IGH in the rear), I will do almost anything to aviod a flat. The current system: Big Apple 2.35" tires, Tuffy type liners, dead tube slit up the inside and wrapped around the actual tube, and sealant in the actual tube. I have gotten flats with this system, but it takes something extreme (3" construction screw or the like). I also ride with a patch kit, tire boots, and a spare tube with sealant preinstalled. Urban industrial areas can be even worse than goatheads. Just a note on the Tuffys; they will wear through the tube eventually and cause a flat, but if they have prevented any flats in the interim, you're still ahead of the game, and they will prevent a lot of them. Also, using an extra, dead tube between the Tuffy and the tube will prevent this, as well as adding another layer of rubber and helping to prevent pinch flats. The best strategy is to keep escalating the prevention until you reach a tolerable level of flat frequency (one to two a year is about it for me). Keep rolling!