Dan:
As an avid walker playing in an area where riding is the rule, any contraption which reduces the use of carts is most welcomed. However, I seriously doubt that IT will make a dent in ridership. For most people, carts are an important part of the golf experience. They get to load their oversized staff bags with 14-20+ clubs, dozens of balls, umbrellas, rain gear, refreshments, etc., and have all sorts of electronics available at their fingertips (phones, Palms, GPS). The riders can dash off to their balls and wait on the people in front of them all the while socializing and/or conducting business. IT would take away from this experience.
While I agree that golf is best played walking, carts have some advantages. When used properly, carts will speed up play considerably. Those folks who ride and play slowly would generally be even slower if they walked. At my home club, we have several 5-somes that can play in well under three hours. Most walking groups have a difficult time playing in less than four hours. I don't think that IT would help the walker all that much. Disabled golfers may also have a more difficult time maneuvering, and unless IT also came with a seat, the problem noted earlier with being on your feet for hours is not overcomed.
Concerning caddies, not only is it difficult to establish a program in many parts of the country, the cost to take a caddy today, $40+, is not insignificant. Carts are here to stay. I just wish that they were not mandatory, and that architects would route courses which were friendly to walkers, make the cart paths less obstrusive, and keep them away from the lines of play.
Dan, congratulations on your decision to pursue the teaching profession. I hope that you are still in the Dallas area. God knows that we need some excellent History teachers here. Good luck!