Answering this takes a matter of faith and a great degree of probability and coincidence I think. I consider that it is likely that a multitude of ATLs spring up with every choice and decision that we make or is forced upon us by outside forces. The PODs around us are constant and in flux, both influencing and being influenced by us. For every right (or wrong) decision I have made when at such a 'crossroad' there are a multitude of other possibilities that were either entirely or partially successful, each to a different degree from the other.
I think in our positions as 'Alternate Historians' we can, if we adequately remove ourselves from the present postulate ATL times for ourselves if we look back upon our lives and identify those PODs, which stand out to ourselves at least, are crucial. For example, if one applies their cold 'Vulcan like' logic, one knows two women, Woman A and Woman B. (The actual sex of the example and subject may differ upon the individual) The individual marries Woman B and after several years have gone by just in passing a conversation of relationships come up. The wife (Woman B) asks the individual if he could ever have been happier had he married someone else.
Sidestepping the point of self-presevation and remaining entirely logical about things, shouldn't the Alternate Historian mention that given the variables know and not known, and given what he knows about both himself and Woman A (the most likely cause of the speculation to begin with) he would (or should) answer YES. No one would say that they will willing renounce their success for proverty, so it can be assumed that one will most likely keep a willing constant move upward.
Okay, perhaps - and most likely - that doesn't make any sense. I think, given our birth, environment, upbringing, etc. that - considering the Present to be a fixed point, that we create the variables which our ATL selves within a predictable range of differences/similarities. With 0 (zero) representing our Present Self our ATL selfs will most likely fall between -5 to +5 (for example) of our Present Self. Undoubtedly if one suffers from an inherited genetic disorder the variable would be even smaller - another example.
One can have a situation where an ATL self is a Hells' Angel, however I feel that it is reasonably possible to estimate a likely outcome and there will be, mostly caused by the influence of outside forces, exceptions.
Perhaps even that doesn't make much sense. In the end right now I would certainly like to believe that there is an Alternate Time Line where an Alternate Self is having a better life. That he has found the happiness that always seems to elude this Present Self.