Frank - I agree in many ways with what you are saying re equipment;
Recently I bought a D2 (with a 6 way blade) and I would say it is a fantastic machine for building golf courses. Most civil engineers would laugh but for our industry especially where we are looking to recreate old type features it is perfect. I did ask on here if anyone had used one and most said it was too small or not used one, I would say you can push 1 tonne at a time. It would get the big thumbs up from me, I would like to practice myself and the same for Ben, I think for wannabe architects, if you could learn to shape using a range of blades it is a big step up for getting on the ladder.
We also added a D4 recently (6 way blade) and we have a D6 currently on hire. I am using Bobby Painter to shape. I would say a D6 can do 95% of a greens construction but it probably needs a smaller machine to finish it off. D6s are perfect for fairways.
My point re Colt or any ODG is that they did not have the bigger machinery we have today. Yes they had better sites but often on a great course there was still a bum/not so good hole, they learned to live with more blind shots, access to modern machines MAY have tarted up a sub standard hole into a better one. A lot of minimalist designers still move 100,000 cube, but it might just be on 3 holes re-enforcing my point that even on a great site 15 holes might fit snuggly but the other 3 need making.