||No offense, but just my personal inner feelings.
Reviewer has unfair review:
-- Agree with leo.anath it is very difficult, But I find "Escalation" process and I have seen it working. Not only because reviewer was favoring but was missed some bad points in winner and saw other thing in second one, when the second contestant re-appealed with his points(including winners submission and his) he was declared as winner lately.
So what I believe is if reviewer is doing review pixel by pixel, we submitter has the option to review pixel by pixel both submission and escalate the against the reviewer if it is unfair review. Definitely his review has to be done pixel by pixel.
hiding the submission:
Personally I do write my handle in the code itself as author, I don't think hiding your submission will really help. If you think some reviewer is favoring to A, then we can't stop (submitter can send the submission id) unless we report to the copilot/PM/admin and upon verification reviewer must be removed from the review board.
So, do your best with your identity, be honest and report to concerned one.