I'm just not seeing the theoretical molten aluminum causing a positive feedback by heating the canister. Small mass, low heat capacity, much of it spatters off, etc.
Here are some sequences I can imagine:
For some reason, the flame is too high (tipped over and fed liquid fuel through the control valve, an over-filled canister got warm and fed liquid fuel through the control valve, a defective control valve allowed too much gaseous fuel out, the valve was left wide open due to cold canister which then warmed up, etc) and the high flame melted the aluminum flux ring. That is thin alumimun - surprisingly thin to me (and I've designed and fabricated more than a few heat exchangers in my professional work) - so in too high a flame, the flux ring may not be able to conduct enough heat to the pot to stay below its melting point.
Or, as suggested by others, if the weld partially fails at the Al/Ti junction, then the heat exchange will reduce GREATLY and those Al fins will approach flame temperature and melt off the pot.
As to a thermal-feedback loop (perhaps due to a wind screen being used?), that would certainly increase pressure in the canister. If velocities through the control valve aren't near sonic velocities*, then more pressure in the canister makes for more fuel flow, a bigger flame and more thermal feedback.
*If they are near sonic velocities, then only the cross-sectional area of the control valve opening matters, more back pressure wouldn't increase the mass flow of fuel. That would be a very safe way to design a maximum burn rate into such a device, but I didn't design this thing, I don't know how Jetboil addressed that issue, if they did at all.
I for one appreciate HJ bringing this issue to my attention - I'd rather know to be alert to such a possibility than be surprised by it on some dark and stormy night. Yeah, HJ gets a little excited about anything related to stoves - that is maybe to be expected in someone with his avocation. My theory is that, like a baby duckling, he imprinted on the first thing he ever saw, but his parents had just left the room and he spied an Optimus 8R nearby.
As for it being improper for anyone to criticize or to question Jetboil's design, I disagree. I had a co-worker who LOVED AMC Pacers. I'd grant him that (1) the things had great visibility in all directions, and (2) he'd never have to pay child support because he'd never "get lucky" while driving a Pacer. But his love of a particular design doesn't mean AMC engineered the thing perfectly and made each and every one of them 100% reliable. From from it.