3) You are only obligated to wing man for one bro per social event, after that the bro is on his own.
This rule is in place to protect the wing man from abuse. And may only apply to the change of setting. The theory behind such a rule is that being a wing man for your bro for any length of time is a full time job. And any distractions from the job can lead to crucial failures at times. So, for instance, if your group decides to leave one bar for another, or hit up that banging party down the street, your bro must designate a new wing man.
Once the setting changes your bro is required to find a new wing man, freeing the previous wing man to hit on chicks or just enjoy the night. If however you wish to sign on for another term as wing man, that is entirely at your discretion.
Being a wing man for your bro is a time honored and highly valued position. It is a sacred trust among bros. When a bro asks you to be his wing man, it is a way of saying that at that exact moment in time, you are the one he trusts the most. Not all bros have excellent game, or can even multitask. Thus the wing man was born, to free a bro up from all responsibilities that may distract him from his girl.
Being a wing man is no light thing. The acceptance of such trust is a heavy responsibility. By accepting the position, you designate that come what may you will remain sober and alert enough to handle everything. "Everything" literally means everything. From another drunk bro throwing up, to your bro's girl's annoying friends, to making sure that one guy you brought with you doesn't get you kicked out.
Many successful missions as a wing man is a glorious thing. To know that it was you who was the papa bro-bear for the night. To know that you diverted and avoided any and all catastrophes, and that single handed, you managed to remain sober enough to do all of this.
A wing man is the guy who made sure that "night to remember" was memorable in all the good ways. A shout out to all you bros who don't grip or whine about the wing man duties. You sirs, are truly good bros.