Marq - my thoughts on that are:

a ) Rustoleum or Tremclad - SAME STUFF.
b ) odorless or regular mineral spirits - ONLY REGULAR MINERAL SPIRITS.
c ) environment temperature - NEVER EFFECTED MY WORK, JUST THE MIXTURE RATIO OF SPIRITS TO PAINT, 2 HOURS DIFFERENCE DRYTIME FROM -10*DEG C, TO +25*DEG C.
d ) environment humidity - QUITE HONESTLY PLAYED NO ROLE IN DRYTIME OR APPLICATION.
e ) even the color you choose seems to require some deviances in the recipe... - ONLY IN THE CASE OF COLOR, SOME COLORS ARE SLIGHTLY MORE TRANSLUCENT THAN OTHERS REQUIRING MORE COVERAGE.

Also i've repeated my results, 6yrs apart, same color, new paint (purchased 6yrs apart) perfect color match. (ie: 69 charger and 74 beetle, both orange.)
That's based soley on my expirences, others results may be different, no animals were killed to paint my car!!!.