Actually I am somewhat of a Robert Moses fan....except that Robert Moses.
* Was corrupt, and used highway building to entrench himself in city government.
* Tried to apply the principles of highway planning to downtown areas, where it disrupted walkable neighborhoods.
Beyond that, I think he had the right idea. Build a fantastic grid of good solid arterials, and connect a freeway through as a "bypass option" to get the traffic that's passing through town off the city streets.
The idea in Provo would be that I-15 is for those passing through, and an eastside/westside beltway would be to get cars that would normally clog streets like University and Center Street onto something designed for cars, opening those streets up for people.
I am an advocate for creating a new major east-west arterial at either 800 North or Bulldog Blvd, and connect that with I-15 rather than building a new Center Street. That gets the cars off Center Street, and opens the street up for what it who it's intended: Pedestrians.
Anyhow, that's how I justify being a freeway nut - but still supporting walkable sections of town.