I feel like I'm missing something: how does this approach speed up calls?
You're still going to want some period of time between the last bid and the "sold" call. (Time often consumed by an auctioneer saying "going once... going twice...".)
Did you reduce that time? Do the other interim calls somehow increase the pace of bidding? What's happening between the last bid and the "sold" call, other than people staring at a timer counting down?