In 2013 you are significantly more likely to be attacked by a jab-cross-hook compo
I doubt it. Why would someone throw a low-strength punch at you unless you had thrown down? If somebody wants to use force on you for some end (kill you, rob you, abduct you, etc), they are not going to waste their time standing in plain virew boxing with you. You are better off learning how to handle unexpected, forceful attacks, and learning how to stay out of fights you can avoid.
It's a valuable thing to learn on the side but too much of it makes you fight, which I think tends to spell trouble.