do you have a strategy for when you take a dump too?
Getting into a fight with an unknown number of people, with unknown motives, and unknown weapons and fighting abilities IS something you should have a strategy for.
When some guy talks shit and gets into your personal space, you have about 1/2 second to decide how to react. If you have already evaluated him for weapons, size, and body mass, as well as counted the number of friends with him, as well as any weapons within close reach, you have a much better chance at suriving what happens next unscathed.
You immediately create space. You get yourself in a defensive position and should he choose to advance, you defend yourself. Avoidance (create space), negotiation ("back the fck up, man", contact (give him everything you've got).
As far as taking a dump, that's pretty straightfwd. however, in a situation where you could lose your front teeth, your freedom, or your life, being prepared isn't a bad thing.