Warm-up:
600 choice

16 x 25 (on :30-:50)
1-4 ez
5-8 mod
9-12 strong
13-16 FAST!

Main Set:
4x [200 Fast from Dive/2 x 50 Swim ez on 1:00]
Or
4x [100 Fast from Dive/2 x 50 swim ez on 1:10-1:20]

400 Pull
-Build each 200

Warm-down:
200 choice