I’ve not felt the need to protect the HX fins on my JB pots. They’re pretty well nestled up in there. A modicum of care when packing should be sufficient for both the HX fins and the other gear in the pack. Now, if one is really jamming gear in there with some force because of the amount of gear in the pack, that’s a bit of a different story.
The idea of using the cup to hold warm water to supply heat to the canister is a good one. Not sure how much water it would hold if there’s a canister in there too, but perhaps enough.
And, yes, the cup would stop air from moving over the HX fins after the stove is off. However, one has to take the pot off the stove and put it in the cup which is presumably sitting on the ground. There might be some heat loss there depending on whether or not the bottom of the HX assembly were in contact with the bottom of the cup which I assume it would be. A foam cozy would insulate better.
A major source of heat loss is through the lid. A cozy over the top of the pot might be really helpful in that regard.
HJ
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