A but OT, but...
The issue with trackless as implemented at WDW isn't as much downtime as it is show resets.
When vehicles lose connection, the ride is evac'd and the vehicles are brought back up. While it is completely possible to get the vehicles back online, verify location, and resume their course while loaded, the mouse's current operations procedures do not allow for this.
With MMRR and Rat, they happen often enough but don't lead to measurable downtime. For Rise, the show control gets all sorts of moody trying to restore effect synchronization, causing bigger headaches.