Actually, you're right because if he punches into the wall and then pushes down as he pushes himself up, he should cut through. Although, he'd already be taking out those claws by the time he would be slashing down and punching them up higher.... so it actually works. Hell, cutting through the wall actually helps his momentum I'd think since it'd take less time to pull out his claws if he just slashes back out and punches back in.
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"COMMUNITY is back at 8 on the 15th. I have a good feeling about those numbers." - Damon Lindelof