Following thread in average 5/10, I think I open this new thread.
Reading decrepit's text:
The rules say, a total distance not greater than 500m and a diversion at the start and finish points no greater than 50m. That's the way Mal conceived it (I think it's Mal's idea).
The GPS we use record data at 1 or 2 second intervals, so it's impossible to get exactly 500m, apart from the very odd time, 500m coincides with a measurement. That may have been Mal's reason for not saying exactly 500m

So no software is lenient on the plus side of 500m. I think I've seen an alpha as low as 70m on realspeed, that wasn't shown on GPSarPro, but I can't tell you what the minimum distances any software allows.

PLEASE FEEL FREE TO WRITE THIS:
1. What than is ideal alpha, what is ideal path, feel free to attach some drawings of perfect alpha.
2. What if that line is not tipical "U" ride then crossline ride ?
3. Anything about perfect alpha is welcome for me
4. Why is @500 "UP TO 500m" when I have in gps results also @250
(what is the difference between these 2 alphas?)
Also I have @1km, I suppose that is kind of long distance alpha, right? 500-500met
THANX IN ADVANCE