Sometimes you take a few steps backwards in life and you take a couple forward as well. Just because you knowingly are behind your PR pace doesn't mean you shouldn't measure where you are at. You go in knowing that you very will might be slower, but if you don't measure, you won't know how far back you are.
If everyone swam at their peak we'd only have a fraction of participation in Masters Swimming. There should also be an element of fun and social enjoyment in these competitions, not just getting PR's and beating our peers.
This morning I got in 2200 yards before swimming Kirsten's workout (which I absolutely loved!!!)
400 warmup - 100 drill, kick, pull, IM
3000 - 3 x (10 x 100's)
First 10 on 1:30 (got 1:15 on all), Second 10 on 1:25 (got 1:12-13 on all), Third set pull on 1:20 (Got 1:08-1:09 on all)100 easy
Then moved northside and did my own frosting set:
400 kick with fins
1000 - 5 x 200's descending pull on 2:40
50 grandpa swimming
7,150 yards total in 2:00