What is the test for following too closely and not being prepared for emergent contingencies?

Using the language of Mr. Justice Wong in Ayers v. Singh the driver in this case acted "abruptly, ...and created a sudden obstacle hazard for those following behind.” The argument that the defendant was following too closely and should have been prepared for emergent contingencies cannot be supported by the evidence. There had been room for the defendant to stop in an emergency, until that space was filled by the claimant. Finally, while I do not accept that there was an ambulance in the vicinity, if there had been the actions of the claimant created more dangers for others travelling around him. When a driver hears a siren or sees an emergency vehicle the rules of the road require him to "yield” to the emergency vehicle. That does not mean stop. Had an ambulance been approaching from behind it might have been in this collision. Section 177 of the Motor Vehicle Act requires that in yielding the roadway to the emergency vehicle a driver must "drive” over to the curb, clear any intersection, and then stop and remain stopped until the emergency vehicle has stopped. When you hear or see an emergency vehicle you try to get as far over to the right as you can and then stop. That is the exact opposite of what the claimant did in this situation.