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@gbj_tester
Let's rearrange Newton:
v²=u²+2as
s=(v²-u²)/2a
Stopping distance is inversely proportional to deceleration.
Although the limit on a bicycle with properly functioning brakes is about 0.6g, IIRC when James Annan *et al *were investigating the disc brake wheel ejection issue, it was concluded that typical riders of average aptitude rarely exceeded 0.3g. For the brakeless fixie skidder, the coefficient of kinetic friction is about 0.5 for rubber on asphalt, and the normal load is rather less than half the system mass, giving a deceleration of up to 0.25g. No amount of skill can increase this. So, ignoring the lengthy period of adjustment to the emergency which is necessary for the fixie skidder (waiting for the cranks to come round to a viable angle to initiate the skid), the most skilful exponent of the art can stop in about 120% of the distance of a nodder on a hybrid, and nearer to 240% of the distance of a skilled rider on a braked bicycle. Since the braked bicycle is not sliding, or even close to it, the rider also has much more directional control and can add evasion to deceleration in order to avoid the hazard.