I am worried that restrictions like this will interfere with what I see as the point of consideration--stopping posts which really shouldn't be on the site (trolls, personal insults and exact duplicats). Just a couple of weeks ago there was a troll who was posting the same stuff (just cut and pasted monastery content which filled the screen without purpose). I considered about 15 posts by this person in a matter of minutes; other people considered the rest of them (there were at least 20 if I remember correctly--I used almost all my daily votes -- them). There were only about 4 people who could consider nodes on at the time. I don't think the problem is the opportunity to consider any number of nodes, but the choices some people make--choices which will still be made regardless of the number of considerations available.

I'm not saying that we shouldn't consider some restrictions. I see it as only a matter of time before a troll gets high enough to consider and fills up considered nodes by considering everything. And of course there is the current problem of people using it to mark things they personally dislike.