Maybe Skritter has too many functions, especially for people who have only just signed, but this one might be quite useful:)
When practicing, I have developed the habit of re-writing every character I get wrong until I can write it with my eyes closed. The part with the eyes closed is perhaps a bit much, but I do think the other part might be useful for an additional functionality. This functionality would be that Skritter automatically erases the character I got wrong and makes me write it again and again until I get it right. I'm very sure that it makes more sense than just looking at it for a few seconds after getting it wrong and then jumping to the next character.
Cheers
David