"You could reduce the problem somewhat very cheaply AND save energy by
insulating the outbound pipe on the water heater."

This will help if the hot water has been recently used. However, if it
hasn't been used for awhile, which frequently happens in places like an
upstairs master bath, it will hardly make any difference at all.

"You can get
fiberglass strip specially made for the purpose for a few dollars from
a home improvement/hardware store. Use latex gloves to avoid itchiness,
"

Fiberglass strips? They sell a foam insulation tube type of product
that comes in sizes specifically made to wrap pipe.

"I also use the leftover fiberglass to insulate the incoming pipe, an
amazing amount of heat leaks out that way and wrapping it preheats the
incoming water, saving you energy. "

Now this is really confusing. Insulation can't preheat anything. And
what amazing amount of heat is leaking out from the incoming water?
Most water coming into homes is from underground, so it's 50 deg or so,
not hot.

" I also agree with collecting the start water in a bucket and using it

to flush,"

Hard to see what that accomplishes. Most places, water is cheap enough
that screwing around to save a half gallon of cold water sure ain't
worth it, cause it costs a tiny fraction of a cent.