Bill, all I can tell you is that we've all had that. The tightness and the transferred soreness I think comes from several things:
- the other parts of the leg / body taking over while the hip grows stronger.
- the incision and manipulation that was done to the muscles
- overcoming the years of compensation the body did for the pain
I taught martial arts for a while, and one of the things I tried to tell new students when they got frustrated by seeing others do the splits when they couldn't touch their toes was that flexibility takes time and patience. Lack of patience leads to injuries that set you back. I've tried to apply that to my recuperation, and my ROM and flexibility, while not back to where they were yet, are coming along.
The Physical therapy was very helpful in that, doing your exercises and eventually the stretches they give you will help a lot. When I went into PT, as an example, my sideway leg stretch was about 30 degrees, which is about 15 degrees below normal. A month and a half later, when I graduated, it was at 55 degrees, which was closer to normal for me.
I've kept up with the stretches, and now with 7 months and 4 months, I am flexible enough, but still have not met my goals. I can put my palms flat on the ground from standing. So things progress if you take it slowly, do the exercises and avoid pain.
I still have some tension, especially in the IT band, so I use a roller to deal with that.