Ally, I am sure it does happen, but like you, it is the exception rather than the rule for me. If I am testing the aerial game, such as "how far can you carry" I am always reminded that 1) I (or pro) is in construction boots on dirt, affecting the swing, 2)I (or the pro) are just one or two data points which may or may not reflect reality, and 3) the weather will be unique that day (perhaps) and if humidity is high/low, wind is normal/not normal, etc. etc. etc. just what does hitting one shot, from one player, on one day really tell us for sure?
In short, while some would say its too "scientific" I would prefer to use what I do really know, as far as actual distance, elevation change (from topos, the eye can be fooled), prevailing wind speed and average direction, carry distance data from the PGA Tour (and maybe to represent the real players, Senior Tour) etc.
Similarly, I have never felt I could predict how a bump and run shot might play by bouncing one over a bunch of clay clods.....Ian Andrew had a blog recently about the slopes on a Redan, where he measured the slope of the green, the kick plate, etc to see what really worked in turf conditons (and even that can change from bent to bermudas, etc) that he will use on any future Redan, and that is where I start, too. If 8% on bent worked last time, for instance, I would start there and modify if I know of some other conditions that might affect it. Hitting a shot on dirt has no reflection on how it might play.
Melvyn, and some others would pine for "the old days" when things were done more by "feel" but I always ask myself if that is really the better way to go in all cases. At some point, all the artistry and design comes down to some little bit of science to convert things to sometimes very precise slope ranges to make things really work.