Fairly commonly, people have the idea that chest breathing is "bad", belly breathing is "good", and that "diaphragm" breathing means expanding the belly.
The Lymphatic System is one of three parts of the body's fluid circulation system, the others being the two way arterial and venous systems. Substances that can't, shouldn't or don't return directly into the blood circulation from the tissues enter the one way lymphatic vessel system. Lymphatic Drainage Therapy (LDT) maps the flow of lymph, identifies where flow is sluggish, and gently encourages improvements.
Your collar bone, like any other part of the body, should move well, otherwise function will be affected either locally or further away. For a contented clavicle, you should be able to float your shoulders upwards, forwards, backwards, and downwards...
Connective Tissue (CT) is continuous throughout the whole body, connecting all of its various components and layers together. It is “Visco-Elastic” - being comprised of Fluid, Elastic and Collagen.
A big ask, I know, but what is simple has been made complicated, and what is unified has been dismantled and disjointed. When it comes to breath, breathing & the diaphragm, I have noticed for many people that this is indeed the case.