I have no experience with the London cab system, but is getting a London black cab license really as difficult as going through a 4-year university degree program (+ whatever 'residency'-type work afterwards)?
[In any case, this is a side point. Most places don't have severe barriers to becoming a cab driver other than limit supply of licenses. And none of that even applies to Uber since they are ignoring that system.]
Getting The Knowledge is pretty hard. Half of the people who try still fail after spending years on it.
In order to qualify as a licensed London taxi driver, a trainee must learn the complex and irregular layout of London's ~25,000 streets (Figure 1) within a 6-mile radius of Charing Cross train station, along with the locations of thousands of places of interest. This spatial learning is known as acquiring “the Knowledge” and typically takes between 3 and 4 years, leading to a stringent set of examinations, called “appearances,” which must be passed in order to obtain an operating license from the Public Carriage Office (PCO, the official London taxi-licensing body).
