video here: https://www.instagram.com/p/BuunEq1n7ey/
It’s an indication that you have good spine health, you have thoracic extension, you have the mobility to not just hit healthy ROM in shoulder flexion, but that you can actually exert force in a flexed/laterally-abducted/rotated shoulder. And in our culture, that basic motion required for this exercise is so absent/undertrained that people have given up on overhead training altogether in some cases.
Per the suggestion of my friend @petertressel, I revisited this lift which I was not able to perform without nerve pain for a few years. With the safety rails placed where they are, I could reposition as needed and avoid the bottom portion which has triggered nerve issues on my left side previously. This is how you can safely bring back the joy of behind-the-neck training.
Given that it went decently, I could foresee reducing load and working the bar all the way down to the traps or even re-attempting behind-the-neck jerks in the not-too-distant future.
For people with certain injuries, imbalances or challenges, start with basic dowel work and examine wall posture checks. If you can’t easily work dowel drills, it would be ill-advised to attempt pressing behind the neck. If you can’t hit basic starter positions with heels, hips, shoulders, head, and forearms simultaneously in contact with the wall behind you, then that will be your goal first. “What are these drills and checks?”, you ask. Stay tuned.
Once you have them, set up a stop-gap like I have here. After that, 200-400lb overhead presses will come next.