Cung Le does fight in Frank Shamrock's Strikeforce organization.
Actually, I've seen fights where Cung Le has knocked people out with his scissor's leg takedown by dropping them on the back of their heads. He can easily use that to transition to a leg lock, like Ryo Chounan's submission on Anderson Silva (leg scissors to reverse heel hook).
He does need to get in there with better fighters to get his ground work tested. He's won quite a few Sabaki challenge matches with submission.
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