If it didn't get hot, the pig skin wouldn't have burned. Is this argument about different fuel or something?
Surely, irrelevant of the fuel creating it, hot is hot is hot? But I'm pretty certain that during summer months, the Bamber AGA would have been turned down to its lowest heat producing capacity. They wouldn't have needed it to heat the kitchen or radiators in other rooms. They wouldn't have needed it for cooking. They probably wouldn't have needed it to heat water. We were told that Boyce carried out his experiment under strict scientific conditions. Exactly how would he have known how hot the Bamber AGA was on that particular night? The only way I can think of is that he started from cold and kept upping the temperature until it burned the pigskin. Might that suggest Nevill was indeed, tortured?