Wirelessly posted (BlackBerry8703e/4.1.0 Profile/MIDP-2.0 Configuration/CLDC-1.1 VendorID/104)

I would never put photocopies of my driver license or passport in my baggage, because of concerns about identity theft. All you need to include is your home (or business) address and telephone contact, plus a copy of your flight itinerary.

Your airline ticket is a contract subject to the terms in effect at the time you and the airline entered into it. So I think it is a good idea to bring copies of the fare rules and lounge access rules with you. While neither guarantees you satisfaction if confronted by an ignorant airline agent, the printouts at least give you something to show to the agent (or to a supervisor), and they might reconsider an incorrect decision when shown the applicable rule. Obviously, you don't want to escalate the situation to the point where jmoliver's nightmare scenario takes hold, but I don't think that you have to be a sheep, either.