Just now, I was able to export a track as GPX on my 66sr. However, the resulting data has much lower apparent accuracy. For example, Lat/Lon in the GPX from BaseCamp have 15 digits to the right of the decimal point; 66sr export has 10. Elevation from BaseCamp has 15 digits, and 66sr export has 2. At least the additional elevation precision from BaseCamp is probably meaningless, though; all of the values are essentially zero after the hundredths place, +/- some noise, so I think this is some kind of conversion error. I would be happy to post one or more of these GPXes from the unit, or the original FIT files, in case anyone is curious, but I really doubt it makes any meaningful difference for the comparison I was trying to do.
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