Great discussion.
If I recall correctly in the Turnberry history book there is an early photo of the first layout with possibly the first green shown and there is a roller beside the green that could only have been pulled by a horse or a team of men. The green has some undulation but is still square so flat and square didn’t necessarily go hand in hand.
I’ve come across newspaper reports from the 1890’s where the writer has complained of greens being laid as flat as a billiard table. It occurs to me that there were perhaps several reasons for greens being laid flat.
Firstly the breed of new golfers didn’t know any better.
Secondly, that in the late 1880’s and 1890’s, in Scotland at least, a lot of the guys who maybe laid the greens and looked after them would have worked on bowling greens. There were significantly more bowling greens than golf greens in Scotland at that time, and the contractors would have been more used to building flat bowling greens.
A third reason might also be that it’s perhaps easier to lay turf and get it to knit together better if there aren’t any contours ? I’m just an office worker so I’ll leave it to others to say whether there is any merit in that argument.
With regards the square shape, I think I’m correct in saying that most greens back then were turfed rather than seeded. Might it not have been easier to lay square/rectangular greens where the turf was rolled out in strips ?
Niall