Well, it was one of the utterly blissful ones. Slightly beyond rational explanation, but as soon as I got in the water everything about the temperature and feeling of the water on my skin just felt absolutely and luxuriously delightful, and swimming was easy and satisfying throughout the workout. (Partly because I did not a single flip turn!)
(I guess I have been slightly swimming-deprived, couldn't go Thursday or Friday because of work conflicts. And because I took Wednesday off altogether, not just for bicycle-procrastination-related reasons but because mid- to late-afternoon I really was not feeling well in a way that asked for food, caffeine, ibuprofen, water and allergy-related nose-blowing rather than exercise, I had to sub in Wednesday's bike-run on Thursday in place of the infinitely more desirable projected long-distance swim at Riverbank.)
Warmup: 800 as 100 freestyle drill, 300 back-breast-back drill-swim by 50, 300 IM kick-drill-swim by 25, 100 freestyle swim
First set (truncated--should have been 24 x 25, 6 each of underwater, kick, drill, swim, split in my case between free and fly): 6 x 25 underwater, 6 x 25 kick with board (3 fly, 3 free), 4 x 25 free on :35
Main set: 3 x 500 with one minute rest, T pace (which is slightly notional to me, but which I was thinking of as strong/harder but sustainable and non-breathlessness-inducing).
Now, unfortunately I was not wearing my Polar watch, and while in theory I should be able to keep track with the clock on the wall, in practice it is so much of a strain on my brain to count laps ("hmmm, that's coming up on 375--or wait, is it only 325? ARGHHHHH!") that though I temporarily sort of register the time when I finish, I cannot really keep track of it even a moment afterwards in my head. But is it possible that my 500s were around 8:40 or so? Seems fast, and yet I think that is what it was.
(But I might have miscounted, must try for a timed hardish one again sometime this next week to see if I am perhaps completely off and it was 9:40 instead! But I do seem to believe they all were around 8:40, I cannot have skipped a 50 or somehow mis-noted and mis-remembered on all three, can I? I am fairly certain the last one was :X8:00-(X+1)6:38 [ED. Have replaced obviously mistaken initial numbers with algebraic symbols, I was only paying attention to the last bit of number...], and that it was pretty much the same in each case... not, I suppose, certain beyond a reasonable doubt...)
(My records suggest that I did a supposed-to-be-timed-500-but-we-stopped-at-450-accidentally very-hard-effort swim in September around 8:40. I was certainly not swimming at nearly such hard effort this time. Today I could have done a couple more at that effort level for sure. And my swimming conditioning must have improved quite a lot since September. But is there really such a big speed difference between my current easy and harder swim paces? I was doing more like 10:20 when I swam those ones the other day--though that really was almost dawdling pace, a stroll rather than anything else.... Hmmm.... )
Then I did 4 x 100, alternating evil drill 100s of right-arm, left-arm, catch-up, free with 100 IM (fly drill).
3100 yards?!? Good, that's quite a lot for me, it was certainly most enjoyable...
[Further ed. It is now nagging at me, this is going to make me crazy--but yes, I took a bit more than a minute rest each time because of wanting to start on a clear interval--it seems to me plausible and vaguely what I remember plus what I can plausibly reconstruct that I might have swum 4:48:00-4:56:38-9, 4:58:00-5:06:3X, 5:08:00-5:16:38. Something like that... I must just stop thinking about this, I will do a timed 500 one day this week and get a better idea, this is absolutely hopeless!]