TD,
Many courses I play, specially the popular daily-fee types, already do something like this quite often. Seldom do I play a course to the scorecard yardage of the back tees. I think the shorter setups are done to speed up play and save on maintenance, not to promote fun as you advocate.
You seem to equate fun with shooting a lower score. As Michael Whitaker noted in your other thread, there appears to be a cultural difference between golfers in the States ('what did you shoot') and the UK ('did you have fun'). If one looks to the game for challenge, as a chance to test oneself against the scorecard and time (historically- what I did last week, last year, a decade ago), and as an opportunity to persevere, scoring higher in a more rigorous examination may very well be superior to a low score on one that has been dumbed down.
BTW, while I've been prohibited from playing the tips on a number of occasions, not once have I been prevented from playing a course from the shortest distances possible. At my prior club, we too used to have a "Red, White, and Blue" tournament and it died years ago for a lack of interest. Perhaps one of the game's allure, at least on this side of the Atlantic, is its inherent difficulty. Maybe unlike for your design associate, a 76 from the tips is more intrinsically rewarding than a 73 from the shorties. Who is to say that one value system is superior to other?
BTW2, when we play your courses, particularly Pacific Dunes and Stone Eagle, are we not in effect already doing what you suggest? Perhaps this approach to golf- shorter courses with more demanding green complexes- will drift our culture in the direction you seek. If not, I am sure your clients will let you know.