Thanks for the answers. I too wondered if Ross had been over credited. But I recall that Herbert Warren Wind article in GD about 1966 (and if anyone here has it and can scan it, I would love to re-read it) waxing poetic about the Ross use of such things in place of bunkers, so I didn't think about it too much.
Richard Mandell credits Ross with starting to mold the surrounds in 1915, and continuing to do so over his career at Pinehurst. There is also mention of the tournament prep and design changes for each of the major events at Pinehurst, where it seems some of those chipping areas really evolved, as late as 1963.
Given how unreliable ground game chipping must have been in the Golden Age, I gather it didn't make much sense then as it would now given modern agronomy. The variety of lies would be a challenge to be sure, and perhaps any little knobs just off the green would affect play considerably, but the idea of a bump and run shot was probably pretty iffy in most situations.
Isn't it odd that some don't credit conditions with keeping the ground game alive or enhancing it, instead of bemoaning how overwatering took it away? In fact, for both fw approach and chipping, the tighter cuts and smoother surfaces are probably better now for ground game than it ever was! And I know most supers keep the approaches as dry as possible, simply because all the mowers turn in that area and wet spots equal tire tracks and depressions, which aren't acceptable.