wonderful post and thanks to all the contributors ! before tackling pashute yid’s post- just a quick word to PM. I (truly) appreciate your erudition and all your insights. You are right in saying that ,as far as melocho goes, there does not sdeem to be a difference between total “kibui’ and lowering a flame- unless both were “oichel nefesh”. I’tll try to discuss the matter of what lowering a flam might be a bit later. I do quibble with your assertion that the Aruch Hashulchan did not know or see elctricity. He lived in Novarduk for 34 years -not exactly a small village and I am pretty sure that he knew all about electricity, in use since the 1880’s. I have not seen the teshuvo that Rabbi Shlom Klass refers to ,of course, so his words cannot be verified but he knew all about electricity. Thnak yo ufor your correction about my allusion to the “Mahrsham”, not the “Mahrashadam”.
It was also gavra-at-work who mentioned that Igros Moshe,see his post. I , myself, am familiar with this approach to a gas line -callin the cutting off of the gas a grama-since the 1960’s. I am not sure that it has penetrated the general discussion but the logic has soem solid ground. I am-BTW- talking about cutting off the supply at the edge of the stove-at the moment of entry.This is how older stoves functioned.It had a line going into the stove and you could turn a bracket to shut off the supply. The logic for calling it gramma is that you are not extinguishing the fireljust starving it of its supply. Not unlike taking away logs on the side of a fire (Pashute yid’s entry)that is clearly a gram kibui.If gacra at work could indicate the place in Igros Moshe, it would be useful. anyway- I’ll try to add to the discussion in a later wntry,as I had the opportunity to review thr Aruch Hashulchan over shabbos. More of that later.