Workout

Warm-up (600)
2 rounds
100 swim/100 drill/100 IM

Set (700)
8 x 50: 2 on :50, 2 on :45, 2 on :40, 2 on :35
4 x 75 on 1:15 
...kick/drill/swim by 25, one of each stroke  

Set (1700)
4 x 25 variable on :30
   #1: hard/easy
   #2: easy/hard
   #3: all easy
   #4: all hard
100 kick
100 75% catch-up drill
4 x 25 sprint on :30

4 x 25 variable on :30
100 kick
100 75% catch-up drill
3 x 50 sprint on 1:00

4 x 25 variable on :30
100 kick
100 75% catch-up drill
2 x 75 sprint on 1:45

4 x 25 variable on :30
100 kick
100 75% catch-up drill
1 x 100 SPRINT

Cool-down (200)
200 EZ choice