This idea was originally floated by Skoda / VW Australia.

The thought train behind this is that when the brake is depressed it cuts out the accelerator signal. Thus pressing the accelerator will have no effect and give the appearance of "no action".

So to put this at rest:

I learnt to drive in a manual and the left foot is used for the clutch.

This is the ONLY use for the left foot.

I was taught that the left foot is NEVER to be used as an alternative for the right foot.

The ONLY time that the left foot is EVER allowed to touch the brake pedal is in an emergency when both feet are slammed onto it.

Our Yeti has no clutch pedal, therefore the left foot gets a nice rest when driving (except when listening to music when it is allowed to tap the footrest in tune with the beat).

So, in summary, I don't left foot brake and don't actually know anyone who does. The only time I could conceive using the left foot to brake would be if the driver had some disability that required them to do so (thinking Walter Jr / Flynn from Breaking Bad here (and I know that it isn’t real life but the scenario is most likely based on a real life example somewhere)).