One thing many people forget (and I'm not referring to any folks on this thread) is that as with any attraction, most hard components are built off site in construction or engineering facilities. Track is bent and welded often by computer), fiberglass is cast and painted, animatronics are built and programmed. Thus, a vast majority of the attraction must be built well before we'll see anything such as a show building rise. The physical buildings don't take long at all. It's the attention to detail that does. So, throw the building up at the last second, ship in and install the parts while simultaneously detail & landscape.
Considering the rumors of vehicle design complexities and the volume of construction in place for the earlier projects (those being built now were further into the design phase I'm sure), there isn't room on site to squeeze in this project yet. Once they begin to clear some of the equipment as the external work begins to wrap up, there will be more space to start this attraction. If we look at the artists conceptions, I can see where the current walls in front of Pooh will have to come much closer to Pooh (and others) to allow for the construction of the Mine. So, if the other FLE work is further along or close to opening, people can be re-routed or simply have more space to walk through other paths. This will be a must during the holidays and next summer.
I'm not an insider on the project, but from a construction/engineering/common sense perspective, this seems to align with what most of you insiders are saying.
