I'm not an expert by any means about this but, innokin mods use straight DC Current instead of PWM, Same as Provari's I believe, so it gives a more consistent power to the atty and stays smooth. Someone correct me if I worded or am wrong about this please!
Mine didn't fully die, but it would go in and out of working, I read about a Fix for it, but was to afraid to try it at the time so I just had the B&M I got it from swap it out. While doing that, I ended up buying a iTaste VTR and haven't used the SVD1 other than to check that it was good to go lol. Funny at first I didn't like the look of box mods but after the VTR it changed my mind completely!
I think your memory is right on that, MC, or mine is off in the same direction!

My guess on the SVD1 is that once the fire button loses its click, it's hard to know when you're actually firing it, and too light a press results in contact bounce, so it shuts off. Irritating, but good enough for the stash box!