Perry:
I think that if one can't score all the entries one should drop out of the vote. Alternatively, if a scorer doesn't score all entries none of his votes should be included.
This suggestion also has been discussed many times before, and I always disagree. If you do that, we will have far fewer scorers.
Remember that this isn't really a contest. It's a way to have fun while we generate new stories and create interest. So we should encourage participation by as many members as possible, even those who don't have the time or desire or devotion to read every story. As long as random readers read and score random stories; even if they don't vote on them all, the law of averages will even things out.
Some folks assign an "average" score to stories that they don't read to help even things out. If that makes you feel better, then do it!