I also saw the original plans for the SS28 plot of SLoP. Although it wasn't a super attraction, I think it had some good quality in the no use of screens approach. Something tells me this will get scaled back just a little when its redesigned for the Globe Theater footprint. I could be wrong, but after Skull Island in Orlando has many trackless problems...why would Universal return to a trackless system?
Forgive the DP, but considering they didn't change the Drupercharged system for Orlando, I would vouch that Trackless can be applied rather well into an attraction that'd be smaller and compact. Not to mention, you were also dealing with truck-sized ride vehicles for Kong and F&F.
I would imagine that there'd easily be a lot of difficulty with doing trackless on that large of a scale, especially from wear/tear and the sensors having to be done in a certain way.