Ford, et. al.:
No, Bill isn't toast because his shack is on the second floor.
ICE correctly instructed him to place the aluminum panel at the
point of entry, at ground level. That is his Single Point Ground.
That said...he's probably 8' or more ABOVE that ground. So for
frequencies of 30MHz, he's .25 wavelength above ground. A lightning
hit will have components at much higher frequencies...so the shack
should be expected to be a voltage node.
The proper procedure, having attended to all reasonable things
at the SPG, is to disconnect everything in the shack....antennas,
power, ground, telephone....whenever there is risk of lightning.
Or...you could be toast. But then...you could be toast with a
close strike, if you were 2' from the SPG, as well!
Protect for whatever you can...disconnect completely whenever you expect
something. It's the only rule that works.
Just be glad you're not on a sailboat. Now THAT'S a gnarly problem.
You can't run, you can't hide, and you can't quit the game.