The ISL is my enemy and I fight back with:
Fresnels with scrim flags,
Neutral density wedges worn sideways,
Very large window-lights with monstrous jagged-edge foam panel gobbos.
Window-size beehive grids,
Backgrounds (and foregrounds) painted dark on the near-side and light on the far-side.
Black flags, Barn-doors, cardboard and anything available that might gradually feather off the light without screwing the shadows (shadows get screwed whenever the flag or barn-door happens parallel to the far side of the window.

That's why round sources or sources with central hotspot are so much kinder to noses, boxes or anything else, for that matter).
In fact, an umbrella with the lamp stuck well inside to avoid spill, and pointed across the subject does a better job with the inverse square law. It is round, has a hotspot (better penumbra and brilliance) and the edges of the brolly feather nicely all by themselves.

But here is the question.
Using a real window and a clear sky. There should be no Inverse Square Law dropping a stop or two at between nine and twelve feet from the window. The sky is at infinity. But it does drop. Like when the window is covered with a sheet of frost. Why?