I remember reading quite a few years ago about an auction process that turned things upside down. Each buyer had a push button, and there was a display at the front that showed a price going from high to low (the opposite of the usual auction where the bidders drive the price up). The auction starts with the price up high, and the displayed price goes down relatively quickly. When one of the buyers pushes their button they win the auction at the price shown on the display at the time the button was pressed. If a buyer presses the button too soon, they may be paying a higher price. If a buyer waits too long another buyer will win the auction.

This process is used for items that are relatively high volume and low cost. The example I saw was for flowers; growers selling to flower shop owners. This process makes it possible to move a lot of product from seller to buyer very quickly.

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?