And another Doh! from my commute on Thursday.

I didn't reset the computer between legs. In the hour and a half I was at the gym, apparently the barometric pressure must've dropped a bit. So my whole return trip was 200 feet "higher" than the outbound leg.

Because it was all one trip, none of the correction algorithms (TC, ST or MB autocorrect) was "smart" enough to correct the elevation data throughout the trip. When I apply MB Gravity, that one is that smart - so my elevation profile is a nice mirror image as it should be for an out-and-back - but it gives me a total elevation gain that's like 40% greater than the autocorrect alone. Hmph.