In the "Confidential Guide" (s) Tom Doak points out many great courses that evolved over time, such as Merion where Flynn and Wilson really added most of bunkers several years later after seeing the course being played, or Woking that was worked on progressively.
However, it seems to me the changes at TPC now are just watering down (dumming down?) the features to make scoring easier. This benefits the owners (the Tour) since the course is less likely to make the pros look foolish - a process that started when the course was built.
Having only played it once, I remember thinking the 12th was an interesting hole with unusual angles, and one of the more unique greens. Wish they could have kept the green.
Several of the most interesting greens were softened, and just from watching about 45 minutes these included #8, #9, #12 and probably others that I haven't focused on. #8 and #9 were really interesting greens.