I don't have a problem with a formula for MLC. Regardless of the source/cause of those, depression + stress seems pretty accurate.
Plus, humans are not designed or equipped to deal with such constant levels of stress. We are able to deal with acute short physicall stress (if we have to run or respond to an emergency situation), but not with prolonged emotional or physical stress. That will cause us a lot of problems, often even leading to a series of illnesses.
Evidently, unless it is illness related, stress comes from external causes. But as soon as it is felt inside body and brain, it becomes an inner issue that will reflect in behaviour, mood, etc. If the person does not change what is causing the stress, the stress is not going to go away, and will remain a brain and body issue.
Stress can easily lead to depression. Depression clouds judgement and way of thinking. Even if the depression came from external factors, it is only depression because it affected the brain, therefore becoming a neurological problem.
I have trouble understanding depression as " deep issues of self in the social world and relationships", probably because I don't really understand the self thing, other than in Jung. And in Jung I see it as a poetry thing.
I read what you wrote Mermaid, but even if the depression comes from any of those things "medications, drugs, alcohol, food" it is the brain and body that process the mechanisms. Regardless where the depression come from, the brain mechanisms are the same, the effect will be the same. what may be different is the treatment/cure. May, because once the brain is firing or not firing, all sorts of things, the game changes.
So, social, genetic, biological, it does not matter, depression is present in MLCers. So is stress.
Burnout is indeed a physiological reaction to stress. And psychological. And it also leads to depression. I know, I suffered from it three times and it always lead to depression. So did Mr J twice before BD. His MLC response to stress and depression is different. Before BD he would crash and have the behaviour that one normally associates with depression, lack of motivations, incapable of getting out of bed, etc.
I have never come across a MLC who is not depressed. The two common denominators seem to be stress and depression. MLC is not a normal crisis. It is not something that leads to a brief crisis mode. It lasts, and lasts and lasts, and while it lasts it adds more things and makes it all much more complicated.
Anyway, in Mr J case he himself said he was depressed pre and after BD. And the doctor from his company confirmed. So, in his case, depression was a fact. And so was stress. The same is true for my cousin, friend and acquaintances who have MLC.
Sometimes good things fall apart so better things can fall together. (Marilyn Monroe)