Workout

Warm-up (600)
2 rounds
150 swim 
100 IM kick 
50 ez swim

Set (900)  
12 x 50 1:10 
IM order:
...3 fly/3 bk/3 brst/3 fr
...evens drill/swim 
12 x 25 :30 
IM order: 
...3 fly/3 bk/3 brst/3 fr
...odds ez, evens fast

Set (1200) 
4 x 200 4:00
  2nd and 4th 50 stroke, IM order by 200
4 x 100
  #1/3 IM, #2/4 EZ free

Set (300)
6 x 50 1:30
...25 all-out 
...25 ez 

Cool-down (200)
200 EZ