An expansion to Disney Springs would not require cutting through Bonnet Creek. WDW (or Reedy Creek) still owns enough land, between Buena Vista Drive and the Bonnet Creek development to facilitate that. In fact, according to an Imagineer that posts on USENET, when Buena Vista Dr was overhauled...
My guess is (and it's more than a guess but I'm not interested in providing references and volumes of proof) that the current track will be completely removed from the concrete base and replaced by new supports and track. I'm guessing that over the years, the current track base has loosened...
There was an article in the Orlando Sentinel some years ago that did some math and tried to show that after Coke pays Disney for advertising and sponsorship(s), and Disney pays Coke for their product, it was almost a break-even, prompting the idea that Disney gets Coke products (syrup) for free...
What if the bus is equipped for <some> programmed motion simulation ? They could then mask the actual road vibrations with simulated blast-off, asteroid avoidance, entering the atmosphere, etc...
My two cents - Vista Way will be demolished and new apartments will built in it's place that will be, at first, connected to Cast Member incentives. Just my opinion folks.