Once again: planning to deploy a weapon without training in both the weapon's use and general hand-to-hand combat skill is foolishness.

I can imagine a couple scenarios that I'd like to inject, one unlikely the other more likely. The first is a 'bikejacking', where someone drags you off your bike from an angle and takes off on it after hitting you a couple times. If crack or meth is a problem in your area this could happen. I doubt it's common, however.

What is, unfortunately common is this: a single male driver, DUI or not, gets in a traffic accident or argument with a cyclist, gets out, and physically attacks. These are two scenarios involving a single attacker on a lone cyclist; one could imagine a (few) more.

A physical assault is two phases: before the assault, and after. Various things are useful before the assault, situational awareness is number one, looking like you aren't bait is number two. Once someone has decided to assault you, and you've failed to detect it, barba's advice breaks down, and you either wing it without knowledge, submit to whatever outrage to your person and property is planned, or revert to your training.

Most people are better off learning to play a musical instrument, cook, make love better...some of us spend awhile learning how to whup people, for our own complicated reasons, one of which is to defend ourselves and/or our loved ones from that sketchy situation that will probably never arrive. All I'm saying is: don't waste your time learning some ineffective form of self defense, and please don't carry a weapon if you don't know how to use it, which includes how to fight barehanded. That's the surest way to turn a mugging into a stabbing, or a vicious beating with your own ASP.