Blade of Wind is way too strong. It requires a extreme skill in chakra control a genin straight out of the academy shouldn't have. Just the description itself should be clear to that.

[quote]his technique is a pinpoint slashing strike, where the user emits chakra from their fingertips and materializes it into an near invisible weapon that assaults the enemy in a gust of wind. If the Sickle Weasel Technique can be regarded as a swarm of wind kunai, then this technique is akin to an unavoidable longsword which can leave the target's body mutilated. Just being in close proximity to the technique can cause minor cuts. The wind blades can be created and thrown, like projectiles, in rapid succession.[/quote]

It's ones thing to know something like Chidori, its one thing to have a rasengan. It's another to have that technique.