Wudan, doesn't your idea make it a pain in the ass to put stuff back together? What exactly is wrong with just adding to the regular code, as long as it's neat and well documented?
ROP, what exactly do multiple checkouts do? Because I'm not quite getting it. How do you have two people checking out one file, and still get the new code from each person when you merge it? Wouldn't one overwrite the other?
Clarionet, n. An instrument of torture operated by a person with cotton in his ears. There are two instruments that are worse than a clarionet -- two clarionets.