Ninja macros

[Fyce]

Macroing the mudras would eliminate the ability to weave them in between GCD abilities and significantly gimp your dps.

From the Preliminary Patch Note:

Ninjutsu
Executes a specific ninjutsu action coinciding with the combination of mudras made immediately beforehand.
If any other ability, spell, or weaponskill is used before the mudras are combined and the ninjutsu executed, the action will fail.
The recast timer will begin cooldown upon ninjutsu execution, or when a mudra timer runs out.
Shares a recast timer with the mudras Ten, Chi, and Jin.

So, yeah, you really can't do anything else beside your Mudras combo before Ninjutsu according to this statement.

That said, since you can't queue up skills with macros, you'll probably have a slight delay on the execution of a complete Ninjutsu art. So, if someone is good enough to remember everything without the use of macros, that NIN will probably have a slight advantage over a macro user.