I think London and New York will be among the few places this bears out. In Seattle many of my trips double, triple, or even quadruple in time if I try to take public transit. EG driving to the Amazon locker for a pickup takes 10 minutes, or 45 minutes by bus. The bus time is for travel time only, and doesn't include time spent waiting.

And trying to get to my SO's house by bus takes a 15 minute trip up to about an hour and a half of walking and transferring.

That's not the case. There are more dense places with good public transport than just NYC and London.

(We shall exclude all of American cities from any consideration, because even in NYC the public transport is pretty bad)

If they don't also have really bad traffic, driving will tend to be significantly faster for most routes. They don't look like Seattle, but they don't look like NYC or London either. That said it's nice to be able to relax and take public transportation and is often a win even if it's a little bit slower, but there's no need to deny that it usually takes at least 10 minutes longer to take public transportation in a place that has good public transportation but not horrendous traffic.

If you're comparing walking, driving and public transport, then at least pick realistic scenarios.

Waterloo to St Pancras will never be a 12 minute drive, even at 4AM - that's practically impossible with the amount of traffic lights.

Let's presume that you're a wealthy Lloyds Group banker(City of London office) living in Holland Park area. Your commute is 35-1:30 by car or 27 minutes by public transport.

Or you're not so wealthy Canary Wharf worker living in Southwark - stable 20 minutes for PT and 30 minutes driving.

At 4am next Tuesday morning Google actually says 9-18 minutes. I assume they have quite a lot of data to model this on, so blame them!

Yeah, but you must also consider that there’s literally nowhere to park you car in St Pancras or Waterloo, and consider the fact that central London is incredibly prone to congestion which gives the driving less predictability.

Right, which makes the data even more surprising! I know I'm reluctant to make a journey by car through central London even if Google maps tells me it's going to be fast.