Depends where you go, Oakwood - Warren Street (11.2 miles according to google) by car ~40 minutes without traffic, with traffic ~1hour. I've done the journey enough times in my lifetime to know. My journey time from my house in Oakwood, to Wembley park is over an hour door to door. Just the train journey, 52 minutes according to tfl and that's with 3 lines. As another fun fact, journey time by public transport for me in Oakwood to Uxbridge(uni) is pretty much equal to your time for central Birmingham to central London by train.
Amp34 quite clearly doesn't know what he's on about. He seemed blissfully unaware of what is available when he made that post in answer to mine. Even though he could have checked it was easily possible. Even more so when Housey it appears uses the same connections I use and have done for years. Kind of backfired in his face though now hasn't it.