It would be really awesome. But people are lazy, and you can never trust people to do it properly on the internet. People don't have the time, are too lazy, they forget about it, or complications arise because of different personalities mash together in a Rping battle thread. No matter how dedicated people are, there will always be things that hinder them from doing things properly. People live in different timezones, they have different senses of responsibility (So that they "forget" to inform people that they can't battle at the agreed time), and so on.
It's a fun and great idea right up until you add internet reality to the picture. =)
In other news, I just opened up a new league. The Dome Wolf League. =)