1. Here's a common comment one reads in this regard (i.e. "how warm is too warm"): if you can't keep your finger on the the canister, it is too warm. Now, I don't really know how valid that "test" really is. Certainly, I would agree with it as stated, but does that mean that if one can keep their finger on a can, that it is 'ok'? That I don't know. I believe that Dr. Caffin has earlier written 105 deg F as a max. temp. I can keep my finger on 105 deg F however. In fact, a quick websearch showed that Californians, amongst others, immerse their entire body in 105 deg F hot tubs - and that's "moist" heat. However, I think that this is perhaps the absolute max temp anyone should use for a hot tub and that "stays" in the tub are of very short duration, but I don't know. 105 seems very high to me for water immersion - core temp will rise quickly, I would imagine. Maybe 101-103 is better??? I would think even core body temp (37C or 98.6F)would feel nice to the skin, but then I've never even dipped a toe in a hot tub, so what do I know?!!! [Hot Tub owners help out here.] So, 105 deg F might be the right number, but most people aren't going to be able to determine 105 deg F with their fingers alone, IMHO.
2. At the risk of allowing the can to cool too much from use, one can use the DrJ "under burner" pie plate, or some similar heavy duty Al shield. This will shield the canister from radiant heat from the burning gas and keep it from getting too hot. But, will it allow it to cool too much for best operation in colder weather since it will not be warmed any by the burning fuel?
Just some thoughts. Anyone have any opinions about these two points?