Does this make any sense? I had a good race on the 28th and then a good workout last night, the 30th, where my HR was a little lower for the power I as doing. The workout was marked as an Xert BREAKTHROUGH on Strava, but this graph strongly disagrees
It has dropped from ~272 to ~245 which is a big big drop. You can get a fakethrough by being a couple of watts so it seems a big penalty for being so close to a BT without making it.