Yeah, I did get an email from you. Sorry I never replied.
I see what you're asking. I haven't really tried to analyze @laonie or @mata, but they're both quite competitive. For a while a few weeks ago, it looked like @mata was the bot to beat, and of course @laonie was the champion for a long long time.
The "how often should you vote" question all comes down to a balancing act. On the inside of my bot is an adaptive model that predicts each post's payout; the correlation between actual payouts and predicted payouts is not great. Here's a scatterplot of the past week (horizontal is my prediction, vertical is actual):
They're obviously correlated (the correlation coefficient is around 0.65), but I can't predict with 100% accuracy how well a post is going to do. So to compensate for that error, I have to spread out my votes over more posts.
If my model were perfect, I'd vote for the best 40 or 50 posts each day and be done. Since my model isn't perfect, I vote for many more. I haven't done nearly as much validation as I'd like to see if I'm actually voting optimally given my model; I have a lot on my plate right now and I just don't have the time. When someone comes along and starts consistently beating me, I'll put some more work into improving the algorithm. :)