I think he's referring to the way that eg lawrencium has a half-life that ~increases with the neutrons in the isotopes we've produced, from seconds for Lr-256 t

I think he's referring to the way that eg lawrencium has a half-life that ~increases with the neutrons in the isotopes we've produced, from seconds for Lr-256 to hours for Lr-266. It isn't crazy to postulate, as a layman, that if we synthesized Lr-276, say, it might have a longer half-life. (Not that we expect that pattern to continue indefinitely, but still, have we discovered the most stable isotope of lawrencium yet?)