Your comment gave me an interesting idea. What would happen if we imposed a minimum char-limit for say, hacker news comments? On one hand I'd expect more descriptive responses, fewer comments that are a short "Your wrong but I won't tell you why", etc. Comments just spamming letters would be fairly easy to detect.

On the other hand what would this minimum char/word length be? Even your comment is fairly short, but it's descriptive and fully communicates your point...