I think what's being suggested isn't so much a null vote that is actually cast with a total effect of zero on the node and -1 on the votes available to the caster (my understanding is that this is what's currently implemented)
Nope, the "null" vote is just that, no vote at all. No decrease in your available votes and no effect on the post's reputation. Its as if you never voted for that node.

In reply to Re: Null Voting--or Undef Voting? by Adam
in thread Trinary Voting by Lexicon

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