Favorite swim workout?

I remember a really great swim session in the London Aquatics Centre during the 2012 Olympics, where me and my friend Louis did a 350m build with an emphasis on the finish. We ended up going 20:50, 24:32, 40:00 Long Course which was a PB for me. We also did 15-20 hours of hard grinds with fast times like 15:25, 24:35, 23:50, and 30:01 all out to get a good time on the last one.
 
Transcript: "Call my favorites room like how I've done a lot of students sessions in my life. I wouldn't even want to bother me, guess how many meters of done. I mean, I start competitive swimming at 9:26. And you know, I'm going for a swim. It's not a Roman. Hopefully, that's the best one. I but one that really stands out, my mind. I was trying to wrap my brain what it could be and we just been in New Yorker for a training camp. We got back me and Louis. We hired a lane, the London Aquatics Center the, the point Stratford that was used for the London, 2012 Olympics and we both really fade towards the end of our 50 freestyle. So we decided to go like 350 to send to push one dive with a build and really emphasizing the finish and we flew like are like 20 50, 24, 320 400 long course, which ended up on point. One off my PB. No suit feeling brilliant. Never recreate that. Right to another training session. But, you know, back in the day. I love the hard grinds as well. Just always like 15, 20 hours of fun 15 off of 245 for faster of 243, faster of 235 too fast on to 30 in one all out to get free stuck in on the last one there."