"On the other hand, it can also be foolish to assume that the reason everybody before you failed at something was because they were all stupider than you."

There's no assumption here. When systems fail, engineers analyze the reasons why, and fix them in their future systems.

I've done some reading on the Denver system. The issues were primarily poor engineering. For example, the bags had to be loaded onto carts a certain way, or they would fall off on the curves. This was poor design: either the carts needed to be better engineered, or the curves should have been less severe.

In some ways, I think the fact that it was baggage, not people, actually hindered the design. If they were designing for humans, they wouldn't have designed a system so fragile.

I've read a lot on PRT, and I've seen nothing about it that is technologically infeasible. There are certainly engineering challenges, but many of them have already been solved. All that remains is some field testing and a commitment to build.

In other words, the main issue that PRT must now overcome is public acceptance, and that's turning out to be the biggest hurdle, by far.