> Front and back brakes on a bike are not there for redundancy. They are components of the same braking system: without both in service, they don't work as well.
Bikes are very different from cars due to the short wheelbase vs high center of gravity.
At moderate or fast speeds maxim deceleration occurs when the front tire applies enough force to lift the rear tires off the pavement thus removing the impact of the rear tires. Below maximum acceleration you could use the rear break but it doesn't do anything applying the front break slightly harder would do.
At sufficiently low speeds the rear tire can help, but it's really there for redundancy as even acting alone it doesn't work very well.
This only applies in ideal conditions (eg: dry tarmac). Where there is less surface friction (wet or icy surface, dirt or gravel trails, etc) you're going to quickly hit the limits of the tire's traction, so will need both brakes if you want to stop in the shortest possible distance.
Wet roads, cold ice, and dirt still provide enough friction to send you over your handlebars at speed. They just increase the maximum speed rear tires provide any benefit. Near its melding point ice isn’t going to provide enough friction for rear breaks to matter.
So sure there’s a minimal benefit in some very specific conditions, but no they are there for redundancy.
Bikes are very different from cars due to the short wheelbase vs high center of gravity.
At moderate or fast speeds maxim deceleration occurs when the front tire applies enough force to lift the rear tires off the pavement thus removing the impact of the rear tires. Below maximum acceleration you could use the rear break but it doesn't do anything applying the front break slightly harder would do.
At sufficiently low speeds the rear tire can help, but it's really there for redundancy as even acting alone it doesn't work very well.