The issue with running a cable across a “driveway” is that it has to be “marked” with either flags or a hanging sign. Otherwise it is not visible. And, at least in my area, this applies to private ways as well. YMMV.
That said, when I was riding...”cut throughs” were always more concerning than just pulling out onto a road because pedestrians and other traffic were not “expecting” you to pop out there.
How much time are you really saving anyway?
He could claim to be saving the planet by saving gas, and money to buy a BEV cycle.