If the drivers are maximizing for time you're not going to sleep very well because they are driving like a maniac. Sudden halts, near misses, and sharp corners make for a particularly terrifying experience when you're attempting to sleep.
The fact that this endeavor is focusing on drivers that go slow is 100% a positive for me and I would now consider trying it.
This is an issue that really just exists with overnight buses, as trains don't make sudden stops and they are not competing with other trains for a lane.