Actually, Warren, I regularly apply Scotchguard (green top) to my 'Stitch. Any Gore-Tex or similar water-proof fabric garment has Gore-Tex (or whatever is similar) bonded to the Cordura (or simillar) exterior fabric. The Gore-Tex lets moisture vapoer pass through the membrane keeping you from feeling like you've been running in a rubber suit). The pores are too large for water to go the other way and soak you from the outside. But for the Gore-Tex to work, the Cordura has to have a Durable Waterproof Protective coating of some sort. Otherwise the Gore-Tex can't "evaporate" your sweat.
I use the Scotchguard green top and spray it on after I wash the 'Stitch. Unfortunately, as near as I can tell, it doesn
not enhance the stain resistance of Rider Wearhouse/Aerostitch Cordura at all. When I look at pictures of what my 'Stitch looked like last summer and what it looks like now, it's obvious that it's time to take a shot at cleaning it again. It'll look better when I'm done, but it will
never look like new.
I consider a stained Hi-Viz 'Stitch as a badge of honor, quickly identifying me to the Lond Distance Riding cognescenti, as a respected member of this exclusive club.
Well, it's one way of not being bugged by the garment's looks. My wife has not been so easily persuaded, BTW, and constantly wishes I'd
really clean it.