Jeff,
Restoration, of course, is site specific. This dissertation simply explains the elements that need to be revived at "Blackacre" to preserve its design interity. Other courses certainly may require different measures of restoration work.
However, you will find that many classic era golf designs do require similar types of restoration. Why? Because of the common evolution of the golf course!
First, it is likely that because of the implimentation of single row irrigation that fairways have been reduced in width and size at your course too. Second, likely your fairways are plush instead of firm. Perhaps through the years there have been some beautification efforts and tree planting committees at your home course as well. Third, bunkers are a high-priced maintenance item, so likely there may have been some covered up or abandoned where you play also. Fourth, because of technology(riding mowers/triplex mowers), I bet your greens have lost there intricate shapes and sizes as well. And finally, I would be surprised if you haven't witnessed a green chairman or two place his own signature on a hole to try to defend par or such. All of the above inevitably affects strategy. All of the above inevitably destroys design integrity and originality. Most all courses inherently evolved this way. Simple as that! So in the restoration business, architects get to cheat, because they know what we are looking for.
Thus, if you want to revive your wide fairways or your green shapes and sizes; if you do want to impliment a tree removal program; if you want to restore some abandoned bunkers, you are right in that the extent or degree of such does depend on the architect and, of course, his client being your membership.
So to answer your questions, there is sort of a formula to restoration that you apply on a case by case basis.
And no, I am not an architect! But I know I would be having alot more fun if I were.