It attempts to reward close finishers and the winner and not penalize unduly early droppers. It would just be one rating number to have along with the win/loss percentage and other stats like entries and current ponds running. I think with the scale I devised and Ed's modification of having a low score show better play, one could come up with a rating that reflects good play and staying power. Instead of using Ed's for a low score, you could use the reciprocal and multiply it by some number, say 1000, and get a number simular to slugging percentage in baseball.
Just to keep track of winners and losers works too BBW, but other ways of tracking players have enterest for some people, just like baseball stats for various things interest some fans but not the ones that only care if their team won the game or not. If both or more ratings and stats are made available, you could look at just the win/loss record of a person you're interested whereas, grenv or someone else might want to check out some other thing about the person's record that you don't care about, but he does. As I said, I wouldn't mind having it stay just as it is, but with so many people clammoring for some kind of rating and others statistics we might as well pitch in and see what we can come up with.
Wins/Losses/Percent of them is easy and straight forward to track. Making a rating system that takes into account how far one goes before dropping out isn't as easy to devise. Plus some people would like to track a player's points along with how many rounds they last and average rounds and percentage of rounds completed out of rounds possible. That's five things to keep track of. Certainly doable, but is that enough or too much? Will those be what people want, or will modification be needed after we get familiar with how those stats look and feel?