There is a reason that Gatorskins are a popular choice among messengers and those who ride fixed and like their skids... they are a relatively lightweight and extremely durable tyre.

One flat is often caused by debris while a second and third might be the result of not finding the offending particulate that caused the first flat... radial tyre wires are one of the most common and worst things to run into and very few tyres will be able to resist something that is so hard and fine that will eventually work it's way through almost any tyre.

My only flats in the past few years have happened while I was riding on Marathons and the Comet Primo's on my folder and the flats happened on the same route which is frequented by large trucks and heavy traffic... have had two flats on the same Marathon with one being radial wirte and the other was caused by a piece of glass as big as my thumb and the Comets were defeated by radial wire but have not had an issue since.

It is almost invisible to the eye and very hard to remove without fairly fine tweezers and is also easy to miss.