The time something was done is a bit of a red herring Paul. It doesn't really matter, nor in a programme like LR does the history order matter that much. Everything is re-editable at any point and you mostly do not really need really need history unless you want to return to a specific state. So if you do a snapshot/VC at every point you think is significant or have 'finished' then you can go 'back in time' that way without worrying about when something was done. History in a programme like LR is quite different from History in a programme like PS where the order things are done can matter.
VCs and snapshots were invented as a better more versatile way of doing what you need, rahter than stepping back through history.
OK now I get it. I will adjust my expectations and change my behavior (take more snapshots) to adjust for this. Thank you for the explanation.