Sunday I hit a new 10min power while holding back a whole bunch, which was neat. Today I tried to hold the same power for 15min and only got 7min in before I knew I was on a garbage day and called it. Then I tried to do a 25min thing at a power I knew I could do cuz I've done it before with ease, and got about 5 minutes in before I had to back off. Promptly went into tourist mode and enjoyed the views for the last hour of the ride. Sometimes you've got it, sometimes you don't!