Continuing on the Tommy Karate mining, I was watching this video and found that Tom explained the inward block in similar way to the way I explain it. If you block with your forearm perpendicular to the floor, it presents the problem of powering your opponent’s next punch. By making some subtle adjustments you can stall that rotation and buy yourself some time. There are some other great pieces of advice in this video in addition to the block explanation, so watch the whole thing even if it is a white belt technique. Of course it wouldn’t be a true martial arts recommendation without me saying I’d do a backfist instead of the back two knuckle punch (or in addition), but that’s the way the world of martial arts works.

This looks very similar to a box-step kempo my dojo teaches at purple belt. After the groin shot, we do a backfist to the face, as you mentioned. We have two possible follow-ups: a side thrust kick that I always feel too close to pull off, or a palm strike to the chin. I love a good backfist-palm combo so I prefer that one.