Originally Posted by RobertHurst

To clarify: in the shortest stops, rear braking is basically irrelevant. But the shortest possible stops are generally not _controlled_ stops. These are stops where the rear tire is not touching the ground, by definition. Not very many people are smooth enough bike handlers to control a stop like that. In the real world, our 'panic stops' tend to be much more subdued, with the rear tire remaining on the ground, and thus able to contribute something to braking, especially when combined with a well-timed body movement.

If the rear can't contribute to braking that means it's not on the ground. You're talking about stops where the rear tire is in the air, and worried about a loss of control from a skid? Anyone who can control a nose-wheelie panic stop could easily control a rear tire skid.

The shortest controlled stops involve use of both brakes. Anyone who doesn't believe this should go out and experiment with front-only versus both-brake stops. It's not even close. You won't need a tape measure to tell the difference.

A rear tire skid should not on its own lead to a loss of control. Something else going on there, I don't know what. In fact you should be able to initiate a rear tire skid and control it, to the left or right, deliberately under quite forceful front-brake deceleration with no thought of crashing because of it. Not that a skidding rear tire is all that helpful for your braking, but, like I said, it's an inevitable by-product of proper 'panic stop' technique and nothing to strike fear in the hearts of men.
Robert