As I understand it, in the FL510 test, a valve simulating the aircraft cabin window is fitted to the emergency exit. At 510, it is opened suddenly to simulate loss of a window at maximum certified altitude. I heard, when opened, the pilots looked at each other and said something like, "is this IT?" Less than 600 fpm cabin rate. An amazing amount of air is pumped into a fuselage to overcome a window failure. Explosive decompression, by definition, is more than a a failure of a normal component, say outflow valve failing open, more like a main cabin door coming off! I know, shutoff a pack at FL450 in a GLEX and you might get a momentary 100 fpm spike as the valves adjust to change in flow
GF