You do know that the Maryland state boundary is the Virginia/West Virginia shoreline. Crossing the center of the bridge would still mean you are in Maryland.
The particulars of the example are irrelevant. The point is well taken.
I was traveling (while carrying) back from NoVa into MoCo this spring, headed towards the Legion Bridge when that tanker overturned, shutting it down. After an apocalyptic traffic jam, we eventually got redirected in a cattle chute all the way down to a DC Potomac crossing, so we could come back up on the Clara Barton or MacArthur/River to get back on the beltway in Maryland.
Which placed me - still absent a DC NR permit - very briefly in DC. One more unfortunate turn of events that day, and I'd be prohibited for life, and maybe writing this from the library computer in prison. That sort of geographic capriciousness should be exactly the sort of thing that any new gun-related legislation includes.