I had to do a few 'studies' in the PATH when I was at U of T for a marketing geography course. Basically the idea of the PATH is to get you hopelessly lost and then make you buy a Yogen Fruz. Ancillary marketing at its best. Think of it like bacteria living next to deep sea vents.
I work with a few people that can navigate the PATH flawlessly. I'm still pretty bad at it and avoid it when I can. I think they designed the weird navigation system so that it would help you get lost. There were lots of complaints from the individual buildings when they instituted the PATH navigation system because they were concerned people would leave their section too easily and shop elsewhere. So some sections do not in fact have any PATH signage. I guess the ******** system was a comprimise to keep people lost. "OH YEAH! RED P IS SOUTH! IT MAKES SO MUCH SENSE!"
Edit:
http://news.bbc.co.uk/2/low/americas/6297149.stm
God help us all. Now the US military has functioning rail guns, heat ray guns, laser weapons and artificial black ice. What the hell.