Thanks for the link. That map makes the Buena Vista Drive entrance seem all the more strange, as the Bonnet Creek property either borders on Osceola or, I'm guessing, comes very close to Osceola Parkway with a thin stip of Disney-owned property between (because if Bonnet Creek actually did front on the parkway, why would WDW have to grant access at all?). That would seem to be the obvious location to build a property entrance - unless for some reason a Osceola Parkway junction was prohibited. I guess what I'm wondering is who controls the parkway at that point, is it a limited-access roadway, etc.? Epcot Center Drive also borders on the corner of the development, as I had assumed.
I don't know, maybe someone in Disney thought a Buena Vista entrance would be the less convenient choice for the development, since you have to go well out of your way to get in or out of the property, except to WDW itself. I'm not sure I would entirely agree with that line of thought, though.