Appreciate the writeup but the 18 to 4 degree drop isn't really the foam doing all that. A 40ft high cube has a ton of thermal mass in those steel walls, so you're mostly seeing the lag from the mass itself, not just the R value. Rigid board done right, taped seams and all, plus furring strips to break the bridge, gets you close to the same numbers and you can still pull panels later if you need to get at a rib or run wire. Spray foam does kill the condensation though, that part you nailed, because it seals the air and no warm moist air hits the cold steel. Condensation on those posts is an air leak problem more than a foam vs board problem.

Ha, that is too good! I had almost the same thing happen with my fiddle leaf fig last spring. I swore the app was a waste of time and only tried it because my wife kept nagging me about the dropping leaves. It told me the light was all wrong and I was watering way too much, and sure enough the thing bounced back in a few weeks. I still give my buddy grief about his plant apps, but I have to admit they know their stuff. Guess we both owe our friends an apology on this one.