[Varyon]

Do note OP is referencing the Clinch Perk (MA51), which is a special case of Skill Adaptation. It explicitly allows you to use Brawling, Boxing, or Karate to grapple, but only against the head, neck, or torso of a standing foe. Personally, I don't feel it should allow for a Head Lock (the only one that could possibly apply given the hit location restrictions) or a throw from a lock (if you do have a grappling skill, but your Clinch-enhanced striking skill is better), but that's probably the GM's call.