Geting back to the original question (with a dose of reality).......
It is my understanding that the Old Course, as we see it today, displays much more of the hand of man than many of us would like to think. If we were able to recreate the landform as it was 2-300 years ago, we would probably find:
--more radical undulations
--few "natural" greensites
--only intermittent grassy areas
--LOTS of gorse, heather and seashells
--tidal intrusion on certain holes
So, do we want to start with that tabula rasa, or assume that we can start with the very different land form which we have today? If we do the former, we will need much more than a lawnmower to make a golf course! If we do the latter, we will be severely constrained by what man has already done to the landscape over the past 2-300 years.
A more interesting (and relatively more practical) "theoretical" would be to ask: "If you had all of the Pilmour Links to work with (i.e. the land on which the Old, New, Eden and Jubilee courses are built), what would you do?"
To really answer this question (and Phillipe's original question) you have to disasociate yourself from the town of St. Andrews and history. Once you put them in the equation, the question is moot, and the answer is "Do nothing, stupid!" Take them out of the equation (i.e. assume that you have this land somewhere in the middle of Kansas, or wherever) and some interesting speculation can occur. But, it can only be speculation.