Andrew,
It may be best understood visually.
Sometimes all you get is a plan, the strategies are usually very clear, but there is no detail. Your only hope is to have part or all of the forms still existing on site.
Quite often we can locate an aerial photo from the early days of the course. This is 1939. We also know there were NINE bunkers already changed in the 7 years before this photo. The one problem with relying on aerial photos is there is no 3D information to help make decisions, all you have is locations.
Some times you end up with a watercolour or illustrated plan produced by someone else. The biggest issue is, did they interpret or worse, was the plan showing proposed changes. We have a renovation plan by Stanley Thompson for Westmount in Kitchener, the renovations are to the course he had built a couple of years before.
The off angle photo is helpful, but a source of trouble too. This shows an unsual side angle of 18, and a far view of the 12th in the background. That is the only existing photo of the 12th hole, that we intend to restore. How do you make decisions based on this? You do, but I hope you understand the limits.
Finally this is the 18th hole from the 150 yard marker in the centre of the fairway. Every hole, at this course, has a photo from this position; and every hole was photographed the first year. It doesn't get any better than that.
Nothing beat the origional landforms still fully intact on site.
I think it is still a better guide than a photo, but the problem is some times its very hard to tell what has been altered.
To fully answer you, you need as much information as you can get to make good decisions. The more you are missing, the more you guess, the less effective the restoration.