Jason,
I was asked to weigh in on this topic since the question of Restoration Vs. Renovation came up regarding Bob O'Link.
Not one of the holes was totally altered from its current routing or any of the routing changed. All 16 greens were mapped and then cored out to remove the old push up soils. New drainage and sand was installed, additionally two greens had been altered in the 80's and were out of character with the rest of the Alison greens. My recommendation was that those two greens be reshaped to more resemble the other 16 greens.
If you walked the course today my hope would be that you wouldn't be able to tell what greens were totally reshaped. The impressive landforms where the greens sit on are as bold as ever. The outstanding work of the two shapers (Jeff and Eric) and Scott the golf course superintendent who in my opinion is one of the reasons the project turned out as well as it did should be mentioned. The committee assembled one heck of a team to complete this project in less than 6 months with some of wettest early summer weather in Chicago in a long time.
All new Irrigation, Drainage, Bunkers, Fairways expanded and native areas added. Plus other infrastructure not directly attached to the golf course itself.
It was a blend of Art and Science with the history of C.H. Alison as our guide.