I just had a conversation with a chap who's putting more insulation in his
attic. I jokingly reminded him to start at 3:00 a.m. to avoid the 135°F
attic temps we've been experiencing locally.

He said "Nah, no problem. I disconnect an A/C duct and let it cool the
attic. Gets it down to about 80-85°. I re-tape the duct when I'm done."

After reassembling the parts of my exploded brain, I calculated he might be
on to something...