I can't honestly say I'm ATGATT. I have, very rarely, ridden without my armored overpants on. Usually in the summer when it's hot and I can't be bothered to put them on. I can literally count the number of times I've done this on two hands.
I've never not worn any other piece of gear. Always full face helmet. Always armored gloves, always armored boots (I like alpinestars boots a lot -- currently have a pair of SMX boots) and always armored jacket. It doesn't get humid here like it does in some places so it's a lot more bearable even in the summer -- really hot days might have me soaking my shirt with cold water before putting the jacket on -- which has a removable liner and lots of zip open vents.
I don't agree that ATGATT is for nancies and wusses. It's for people who know how much the asphalt hurts and would like to do everything they can to MITIGATE the risks. We all know motorcycling is somewhat risky. Different people are willing to accept different levels of risk. As long as somebody is educated about the risks and takes whatever steps THEY are comfortable with, I don't give a rat's ass what you wear (or don't).
What drives me bonkers are the morons who don't realize the risks they are assuming by not wearing gear. Not everyone who doesn't wear gear is doing this -- some know full well what the results can be. But far too many people don't -- they just think "well I won't crash. Haven't yet." Yeah, well, nobody plans on crashing. And you can certainly control yourself, but you can't control the other people on the road.
You couldn't hear a dump truck driving through a nitro glycerin plant!
Badasses might screw with another badass. Nobody screws with a nut job.