srothstein wrote: ...In real life, the new version of the federal law has not been challenged and possibly not even used...
A technical quibble. The "new improved" GFSZA has indeed been used
and challenged, on the grounds that Congress exceeded its authority under the commerce clause. None of the challenges I know of have made it past the Federal Circuit courts -- all have unanimously ruled that that little "jurisdictional element" that congress added to the original GFSZA cured its constitutional defects. I summarized a couple of these, with links, in another thread around here someplace.
In general, feds have charged GFSZA violations as add-ons to something else. There is one case where a CHL holder (in Alabama) was charged with having a gun within 1000' of an Alabama school under the GFSZA, and the circuit court overturned his conviction because he did have a valid CHL (or whatever Alabama calls it). That did not "overturn" the GFSZA; it confirmed it, because one of the exceptions is for a person who has a CHL from the same state that the school is in.
Basically, if Congress mumbles something about "used in interstate commerce" in a law, commerce clause restrictions go away. Congress's ability to regulate anything is pretty much unchecked.