It doesn't matter if he grapples or not if you set it up or hurt him then hit it with it or so he lest expected it. Its a damaging kick ass technique ask your buddy MMAist (I'm a fan of his, very skilled standin & ground) Vitor Belfort, drop him like its hot fight over, pretty much.
Thats what I've experience vs. people that are not in as good as shape as Vitor but still thought they were tough.
The spin back kick (I'm still not a fan of the SS) is the body slam of kicks, its the RNC of standing kicks. I've seen people get their ribs broke just sparring with it & knocked over tables with it!!!
Used properly and at the right time it's far more powerful then your left hook, if you can imagine that Chen.
Ask Vitor Belfort next time you see him
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