This is a tangent, so hold on, but it is related to the post by
Doge
I wish bike GPS's would move away from climate based elevation estimation and use instead a slope based measure. If you have distance, time, slope...........you've got elevation.
Just have the bike GPS zero itself on level ground in your house (assuming you don't own a piece of crap that's super not level).
I feel like the granularity of a climate based elevation sensor does not pickup a lot of the little 5', 10', or even maybe 15' little oddities on some routes. It also probably tosses in weird changes in weather tossing the elevation off.
I see people with the SAME gps units on group rides of 25mi and 1500 feet arrive back with differences person to person of up to 300 feet. That's 20 freaking percent. That's silly.