My understanding is that VO2max is a corralary (sp) and not a cause of high aerobic performance. It's not how much oxegen you take in it's what you do with it that counts. I think the limiting factors are much more likely to be capillary, mitochondia density, and the efficiency of the neuro muscular conections. Another point is that VO2max is not even an indicator of high performance it's the % of VO2max that your AT sits at that is the more meaningful number. I seem to remember the power running site has a bit to say about this if you have'nt already checked it out I highly recomend it.
BTW I have no idea who you are, whats your background?
Yes you are right, VO2max is more a measure of aerobic potential rather than of current aerobic ability.
As you say, performance in any given event is usually dependent upon many phsiological variables. In most normal endurance events, with a high VO2max one is simply more likely to succeed with the right training.
I know very little about neuro-muscular connection limitations... I think I remember writing a really boring essay once on acetyl-choline as a potential site of peripheral fatigue!
Capillary density and the extent of mitochondrial reticulum development are of course both very responsive to endurance training. Improving mitochondrial development beyond a certain stage does not appear to raise the fiber's QO2, thereafter the increased density appears to be related mainly to improved glycogen sparing via lipolysis.
My background... nothing special!