You don't get that kind of accuracy in any system that has to deal with congested roads, or any dense major city. E.g. there's plenty of bus-stops near me where stops on the same route involves going around corners and traffic machines and stopping close enough that GPS would be insufficient to be guaranteed to tell the stops apart if you don't get a good enough fix on additional satellites quickly enough.

Even with all the extra data, and a lot number crunching, in London it's a challenge to get it to withing a few minutes during rush hour.

So, sure, if you're dealing with simple, small systems with little congestion, you can simplify.