ESPN's Dan Graziano provided more context, explaining how the pro day is part of a longer predraft process with Lance:
It seems likely San Francisco will select a quarterback with the No. 3 overall pick, even with Jimmy Garoppolo still under contract. A team generally doesn't swap first-round picks and give up its next two first-rounders unless it's attempting to find its quarterback of the future.
The intrigue stems from who will arrive in the Bay Area.
Between that and the fact the 49ers already traded up, there's little need for Shanahan and Lynch to engage in any of the subterfuge often common for NFL personnel around the draft. San Francisco will have its choice of Lance, Justin Fields or Mac Jones.
Fields got the nod in the B/R NFL Scouting Department's most recent mock draft, and ESPN's Mel Kiper Jr. projected Jones to be the guy. But there's little reason to believe the franchise's interest in Lance is anything but genuine and would signal a continued level of indecision.