I've long settled on interpreting the meaning of upvotes as "I like this post and want to see more like this".

I vote on posts before knowing who authored them or what their current score is, using the Anti-Kibitz script. This is because I've become more aware of my own bias as a result of reading LW, which I believe was the intended result. (I liked Yvain's post and voted it up, but not because I'm a "fan", just because I thought it'd be nice to have more posts like it.)

After I vote a post up, I turn off the script to see who it was from. If I thought they deserved an upvote in the first place, my vote still means the same, and it's natural to wish that my vote aggregates with others' in giving the author feedback about their post. So, I don't as a rule go back on a vote once I've given it.

So it kind of puzzles me why you seem to think there should be some kind of "vote ceiling", or why you expect that your own evaluation of a post should be a good indicator of how others like it. What I'm saying, I guess, is that I don't get the point of your parenthetical.

What would you want us to adopt as a voting norm?