schreef ...

Sorry, but I still don't understand this. Braking with the front brake
won't directly result in tending to turn the handlebar. What may happen is
that if you brake strongly then the deceleration tends to push your body
forward on the bike and you push against the handlebar.

You're right. My description was not correct.

This would be
equally true whether the deceleration is caused by braking with the front
or the rear brake. The only difference is that the front brake works
better so it can create greater deceleration - but you can certainly use it
gently as well.

One can, but I feel I can control the steering better when applying the
rear brake with my left hand. I think it has something to do with the
steering being slightly impeded by the braking forces on the front
wheel. When using the rear brake, there is no braking influence on the
front wheel.

I'd much rather have control of the brake that can stop me quickly even if
that means I have to be careful not to lose control than to only control
the brake that can stop me much more slowly.

I'd say: try it for yourself. I did and prefer the left hand/ rear brake
setup. Works for me and I'm still in one piece - as is the dog ;-)

--
Regards,
Marten