Innue said
Hiden are things like the Nara techniques. Technically others can learn them, but they are closely guarded secrets so it doesn't (or rarely) happens.
Actually, with the war and all, and clans being nearly killed off... they might be a LITTLE more willing to teach their Hiden in an effort to gain and adopt new shinobi into their clans and strengthen their numbers. I know I'mma teach away some Hozuki-Clan Jutsu for that very reason.
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@Marrow: I meant "Water". Shut up, I'm still sleepy.
But yeah, me no know what those jutsu are without clicking... and my browser is being a bastard with hyperlinks lately.
In any case, japanese or english, it's really your call. As I said, those weren't formal reviews.