Hello, "oddball". (I thinks that's your user ID...sorry if I got it wrong).
You are right on all accounts except that I do believe that the thickness of the product is one of the factors that makes it last. On all areas of my home where there isn't snow accumulation sitting on the paint, and splash back from rain splashing off the roof onto the exterior wall shingles, the product has workked exceedingly well. My whole point, however, is that the guaranty says ":LIFETIME AND TRANSFERRABLE". If there is failure, then they have to honor the guaranty no matter where the problem is on the house. If they promise it, I EXPECT it!
Now, did they prepare the surfaces well? Well they sand blasted every square inch of old paint off the place. I think my problem comes in with the workmanship in that I found places that weren't primed at all, and places, like above the garage doors, where it had rained the day or 2 before, where I assume the shingles were still wet after the stripping. I was at work when much of thr work was dons so I suspect that's when the "games" began. When the cat's away...the mice will play...Potentially, I have high hopes that we will get many years still out of the job, I'm not totally confident though but I was able (with considerable wrangling for months) to finally get a painter out here to scrape and paint (did a poor job...but I couldn't be fussy at that point!!)
My advice to anyone getting a spray on siding job, check the recommendations, references and even BBB. Make sure the work is done in decent (not cold) weather and several days AFTER rain so things have had a chance to dry out, and WATCH the painters every minute because they tend to "overlook things" (like primer in spots around my home). I made it my mission, when I was home and the painters were here, to go over every inch visually, using the excuse of bringing out Cokes and brownies and even sandwiches. Feed them, keep them happy and watch them like a hawk. Let's face it, they don't care how well the work is done...they are after the bucks.