I'd much rather see them calling me for rides, or using the Public Transit system we have here in Denver. It's a great system, alot of people don't realize how convenient it can be. Also, the elderly that DO pass the driving test could help out those that didn't and give them rides that way. I would really like to see something like this happen in the near future. I'm sure by the time my generation gets to a level of power, this will become an interest.
The elderly are just such a risk when it comes to situations like this. Sure they can drive straight and turn, especially when they are forced to focus on the road with an instructor next to them, so they might still be able to pass a driving test. But what worries me is when it comes crunch time, and something unexpected happens, or if they are even slightly distracted. These situations should be incorporated into the driving test, then licenses can be re issued if they are competent enough to handle an unexpected maneuver.
I've seen and heard of many incidents(like this one) where it takes the littlest thing to distract them, or they just plum aren't paying attention, and all of a sudden they are slowly drifting to a curb full of people, they are accidentally running a red light, that sort of thing.