Not where I live...in west London if you leave 1 car length + 1 inch ....you'll have someone in there...usually cutting through to get onto the slip road which is full of traffic that they don't want to wait in line for....so they cut in and hit the breaks too!
Generally it's a Merc, bmw or Audi...not always but mostly!
But that as I know is the way one has to drive in London. Indicate your intention then do it. Hesitation will confuse and if you wait politely to be invited, you'll be there all day. Any other city, someone will take umbrage.
Indicate? That's so last Century!
I think he means telepathically.