[RiderofBikes]

wmjinman,

No i get where your coming from, and it's as simple as what were doing these days already.
Albeit, You don't need crazy individual "precise" statistics to find something out. The fact the Current Basis way of testing includes all the variables. Which convenient, could still have a greater margin.

What i'm simply referring too, is to the point where, at what detail circumstance can you inform yourself that this is optimum? Pure EV's would have a greater significant +/- range issue based on Temps, not so much elevation tho(unless your climbing).

With your previous experience as an Surveyor, If it LOOKS right, is a tool for all of us used here and on our projects anyways. You probably weren't paid to just lolligag around either, requiring you to not be so "precise" but within the constraints of whatever your task was. Not everyone is lucky enough to have such consistant results, so your obviously doing something right overall.

Lets say,(Pre warm up of all parts both tests) You result 1.3mpg increase with higher tire pressure at Ambient 80-85* without any other extreme variables mixed in.. Then Test the same psi during Ambient 25-30*(without any other "stuff on the road ways" to compromise RR), would Estimate only a 0.9mpg increase?

Of course, I specifically don't know that for sure... It's just a hypothesis to me(to anyone who doesn't know, especially, when types/brands/tire sizes are compared), given nature being much more forgiving in higher temps than in cold, excluding Warm-up times. Who knows, maybe the temp doesn't make a difference?
Maybe comparable "LRR" tires, same size, used on same vehicle under silmilar circumstances, X Brand has .3mpg loss given temps, compared to Y Brand having .8mpg loss due to temp.

There may be a trend in results when it covers more detail than just a 1 day testing including (X variables).