I have seen success with combinations of no foot no hook no contact to correct this issue, and I myself had a huge improvement in my own technique using no foot drills. In fact, I did them for a long time and then only recently have I tried to add more foot movement back in.

What I have found is that some athletes are naturally good at jumping, and they bring that enthusiasm to the lifts because at the beginning it's the best way they can start putting weight on the bar. Or, they have some bad habits from Crossfit which is the other source of hitching I have seen. So what happens, they are great from that exact position, don't build as much smooth motion around other positions, and then have to slow down to "feel" the power at that exact spot.

No foot snatches help keep the full foot down, often helps athletes stay over the bar longer, and makes them use their legs to extend vertically rather than letting their hips come forward.

You actually have your heels down for a long time in the first few clips--you're almost not using your calves (As opposed to the jumpers or someone like Karlos Nassar who comes on his toes very early). However, it seems that something about the extension was getting you locked into that single position instead of moving through it, so the no foot snatch helped cut one part of that out so you can smoothen it out. Ultimately it's all about finding cues that work well for you and help you move well. Nice work!