Zig Zag, is pretymuch usless,the best bet is simply to change heading radicaly and repeadealy while the buff is almost to drop point, ya see, when I am in a buff I look at the outer destroyer to see whear it is going this tells whear the cv will"be" so i can drop in its path even if it is turning, so Zig zag's not realy the answer, the buf could arive over target when it is on a streight course, or on a turn, and if the guy knows his stuff even if it is turning he can hit it, it is the turn that is excuted that he has no time to counter that will save the CV.
Howeaver if the CV is being JABO'ed to death, aka Sucide mishion...their is no defence.