[drcy]

With Pre-certified lots, you pay for a physical LOA if you want it. You can instead use a copy of the auction listing as equivalent to show the autograph(s) were pre-certified. The auction catalog description can be used as documentation the autographs were pre-certified, and I know of eBay dealers who do just that.

I would imagine that the pre-certification method was the authenticators' idea not the auction houses'.