Yes, letting off the pressure is important. I forgot to mention that.

The pump that was to be taken out of the fuel bottle when stored was on the very first MSR stove invented by Larry Penberthy in early 70s. It only took them a few months or a year to come up with the improved "leave it in the bottle" pump.....if I'm recalling all of this correctly.

That very first stove, by the way, was like a blow torch. They let us trade it in, at no cost, for a later model that simmered better. I traded it in but never was able to boil water as fast as I could with the very first one they came out with.