"Some forum posts state that it only is effective against physical damage. "

What posts? Link? Gettingbetter 15:06, 29 August 2008 (PDT)

And what's the story with Ninjitsu & Bushido, either it's required or it isn't? Is it a special weapon move or a skill move? --Ceruleus 20:00, 18 March 2009 (UTC)

When the SE and ML expansions hit, new special moves were introduced to accompany the new weapons. In the case of the SE abilities, they tend to demand minimum Ninja/Samurai skill levels in addition to the usual "combat skill" requirements, but they still function the same as a regular special move in that you only have access to it with the weapon equipped.
Think of it sorta like Shadowstrike, where you can have all the weapon skill in the world but it's no good to you if you can't stealth.
I'll take a stab at explaining this on the Special Moves article, but really the individual moves pages need some more info on exactly how much skill each requires. - Bomb Bloke 23:59, 18 March 2009 (UTC)