Could also be you stopped a little short of where the segment ended (or at least your Garmin reported that) while your friend did complete the segment when he reached you. After resting almost 2 minutes, both of you descended together. Easiest way to check for that is if you select your effort on that segment and Analyze Effort to see if you have your speed dipping to zero near the end before rising again right at the end (works on smartphone, not sure if desktop/web shows the same data).


Over here, we have this one climb where the uphill segment ends somewhere past the peak, and the downhill segment starts before the peak. So if you stop at the peak (either to rest or to wait for friends), your segment times are screwed both uphill and downhill, and they way they overlap you can only ever choose to attain good times on one or the other unless you do not stop at all.