The 5th at WS is pretty much a result of a wetlands "trade" (remember Bush I's "no net loss of wetlands" policy?). A small portion of wetlands on the area Dye routed for the course was traded for the wetlands surrounding #5. Dye, in interviews leading up to the PGA, acknowledged the hole was somewhat out of character with the rest of the course, but said without it, the course would not have been built.
It gave Loren Roberts, in contention for the US Senior Open last year at WS, a lot of trouble. I haven't played it, but it looks like it has semi-blind landing aspects to both the drive and second shot.