Board Thread:Special Events/@comment-25730832-20150801135420/@comment-26705246-20150826222023

Probably because CEGHLZ on medium only has a 50% to encounter a Tsu-class normal before the boss, while CEGFJKZ will encounter a Tsu-class normal and has a 50% chance to encounter a Tsu-class elite before the boss.

If you are using a CTF, then you'd generally prefer to mess with a Ta-class FS which has a better chance of missing than a Tsu-class has of not triggering AACI and depleting your bombers.

Even it your CV(L)s are moderately damaged, they can still partake in the opening airstrike if they have bombers. Thanks to the 1-2 Tsu-class (one of them as elite with greater AACI capacity) encounters on CEGFJKZ, plus the guaranteed Tsu-class on the boss node might mean your CV(L) being unable to attack at the boss due to the fact all your bombers have been shot down, regardless of health.