I'd point out that Hyperion Wharf is a different thing, requiring the cooperation of interested tenants. Whereas if WDW said I really want to build an attraction they could get it done at a reasonable speed. Compare that to trying to round up several different retailers and restaurants who were spooked after a recession. Also it appears Hyperion Wharf was a smaller more contained refurb, whereas Disney Springs is a radical redo of the entire area. It's really an apples to oranges comparison.
A comparison was made between the somewhat lurching on-again-off-again-on-again approach to developing Hyperion/Disney Springs and attractions like Monsters Inc. and I think it is a fair one.
Yes they could plan, announce and build an attraction a reasonable speed but they almost never do. The lurching approach is apparent in practically every non-DVC construction program at WDW: Hyperion/Springs, Monsters Inc,
Pixar Place, Star Wars, Avatar, New Fantasy Land.
The only outlier is Frozen Fo'Evah which was probably viewed as a hands-down no-brainer money grab. And to be honest, it doesn't even count as a new ride. Compared to a new ride, it's more like the makeover of the Pirates attraction to include Johnny Depp, Davey Jones and the Pirate training academy. A couple of new AAs, some video effects, a meet and greet, and toy sales. Ba-da-bing, ka-ching.
It's an interesting and significant piece of NewSpeak that Disney decided to re-christen the lurching approach to theme park development "extreme deliberation" ... in Iger's statement on the much-expected and much-ballyhooed Star Wars Land. Call it what you like, Bob. I'll be down the road checking out the new rides at Universal, SeaWorld and Busch while you're, ah, deliberating.