Paddling harder ≠ going faster

I paddled the K1 for 60 minutes this afternoon.  After warming up I did six 12-stroke sprints and then timed myself from the monorail bridge to the Hernando DeSoto Bridge.  My time was 2:10, and I was disappointed because my split at the HDB was 2:05 during both those pieces from the monorail to the Auction bridge that I did last Saturday.  But I've known for a long time that a law of diminishing returns is in effect when it comes to how hard you paddle, and I hope these higher-intensity paddling sessions will help my race pace later on.