Cool post, I can really relate to the tightness point having blown both of my Achilles tendons. I means it takes quite a detached state of being to exert the body to such an extent.
I visited one guy dealing with body adjustments and he suggested a very simplistic and commonsensical thing which i overlooked - to give some daily care, especially for the newly injured tendon, by applying a bit of oil and doing some massage. I did it for a while and that felt really cool.
So yeah the point of caring for self to no longer get into such situations is of utmost importance for me at the moment