I do now use two brakes again. However, I remember locking up the rear wheel a little alarmingly when I (over-)used both pedals and brake together. I had, not too long before, watched our car going through its MoT, and had the mechanic explain why they ensure that the braking power on the front is substantially greater than the rear (which is fairly obvious).
It does give me pause for thought that, on a vehicle on which stability is essential, we do it the other way around and put two brakes on the back.