Ok let's sum some points up here:
- Yes, it is possible to charge a battery quickly
- Yes, it is possible to run other configurations safely
- Yes, it is possible to charge multiple batteries at once
- Yes, it will damage your overall battery life.
Moral of the story? Be patient and protect your investment. It's not worth the risk of charging a battery really fast for one match and then having it kick out completely on you later in the day (when you really need it)