yeah, i figured better left alone, and my concusion on it all..which was, a definitive...
MAYBE!
i can think of a ton of other tonal options that i'd rather experiment with before splitting these types of hairs...but, to each his own, and my ear is different than your ear, etc. keeping the heat in on an amp head, well, obviously the heat is going to escape out the top, as heat rises.
on a combo...maybe they help things heat up quicker, as the combo tubes in my amp hang upside down and the air wouldn't escape as easily...so, whatever effect highter temps on pretubes has over a longer period of run time, then, i wont argue against someone hearing a difference because of them.
my tube covers have springs loaded inside them and it seems they were meant to keep the tubes from vibrating loose and feeding back because of the vibration.
so, maybe. too many variables, and, again, splitting hairs, imho at that level..but, to each 'dey own.
