"My sense is that if I use the proxy system it may induce a race to $200 but that if I put in a big bet it may discourage someone..." Travis Lewin

Travis; If you put in a big bet (bid) of say $200, nobody would know it. Any bids submitted above the current bid level would receive the notification "sorry you have been outbid .... ". This notification would continue each time a new bid is submitted until someone topped your $200 bid. Only at that point would anyone know that your top bid was $200.