Chris:
Actually quite a lot of my courses begin with par-5 holes: Stonewall Old, Barnbougle Dunes, and St. Andrews Beach all start with a par five, in addition to the courses you named.
But the funny thing is, I am not really that big a fan of par five opening holes. As a player one of my goals was always to try and keep a six off my card, and when you put a par five as the first hole, you tempt fate early. You don't want to make it too short because that will slow down play off the first tee [George Thomas apparently never anticipated that his courses would have eight-minute tee times]. But you don't want to make it too tough and get a six on the card right out of the blocks, either. The first at Black Forest would be a great hole later in the round, but as the first, I have found it VERY frustrating.
I prefer a par four to start, and I think that my best opening holes so far fall into that category. I wouldn't even mind a par-three opener -- I've seen a few good ones -- but I've never had a client that would even consider it. But the fact that I've built so many par five openers should tell you that I really do let the land have a lot to say about the routings of my courses.
Bill M: Yes, there are a few MacKenzie courses that start with par fives, but you named a high percentage of them right there. I certainly don't think he favored par fives, if you include Augusta and Cypress Point and Royal Melbourne and Crystal Downs in your thinking, all of those start with strong par fours. Coincidentally, though, on all but the last the second hole IS a par five.