These are a few of the things, I've been trying/seeing in my practice that I find pretty interesting.
I've found that when I treat the external rotatores in the shoulder cuff, the contralateral scalenes seem to relax quite a bit more.
Bringing the strength back to the supraspinatous muscle has the majority of the time let the upper trap relax and get soft. Obviously this is the brain keeping the upper trap tight to either protect the shoulder, or give the deltoid help with movement. Again, why I think most upper trap stretching is worthless.
Working through the tissue around peronius tertius and extensor digitorum with soft tissue work (active release technique) seems to help free up superficial peroneal nerve. This has really helped restore general tightness in the lower leg and increase dorsiflexion.
I have been treating the gastroc in the same treatment session as the psoas. The tight gastroc seems to make the psoas work harder. If the calf is tight, the initial pop off the ground isn't as strong, body feels like it has to use more hip flexion to achieve ambulation.
See if you find any of these patterns in your practice or on yourself.