Its meaningless to compare Tengah to a car heavy matured estate with over crowding stations. I am sure its not HDB or LTA intend to develop Tengah MRT stations to be as crowded as Bishan or AMK.we can see you really love LRTs, but the math doesn't support that Tengah can't survive without LRT.
you quote 45000 households for Tengah and postulate that autonomous vehicles (which include driverless buses) plus the 3 MRT stations can't handle the number of people. Here's some data for perspective (data from Singstat 2010):
AMK has 60,000 households and only 2 MRT stations.
Bishan (which is supposedly about the same size as Tengah) has 27,000 households and 1 MRT station.
Toa Payoh has 43,000 households with 3 MRT stations.
Yishun has 54,000 households with 2 MRT stations.
(Yes, the NSL has a higher capacity...)
Sadly, you have little confidence in autonomous vehicles and adore LRTs. Ironically, LRT is an autonomous type of transport, only difference is that it is above ground and does not contribute to road traffic. With Tengah designed to be car-lite, with a proper approach to traffic management, there should be no problems for autonomous vehicles to be better than LRT. Besides, the LRT tracks also take up space that could otherwise be more lanes on the road.