You could macro them, but the delay between the mudras just isnt worth it. I don't use macros like this anyway, but I was curious. Trying to spam the macro without a wait command doesn't really work either. It's also odd that I can't get ninjutsu to work as a macro at all. I've tried:
/ac "Ninjutsu"
and
/ac "Ninjutsu" <t>

Anyway, there is one macro I do find useful:
/micon "Chi"

The regular ninjutsu skill doesn't light up when it's ready to use and that bugs me to no end. On the other hand the mudra skills do light up, and share the same cooldown timer as the ninjutsu after the cast (at least, so far they have).