[Rockingham]

Instead of not being able to "turn back the clock," I would put it as that even God cannot undo the past. See the Book of Job.

Under my projected revival of dual federalism concepts, matters involving local police powers without an appreciable impact on federal commerce ought to be beyond the scope of the federal commerce clause.

In one example, under the commerce clause, the federal government might comprehensively regulate commerce in dynamite but could not in isolation of such a scheme pass a law that prohibited the stockpiling of dynamite within a hundred feet of a school.

Nor could the federal government use the commerce clause to comprehensively regulate education, but it could regulate educational credentialing so as to prevent diploma fraud and prohibit diploma mills or it could make safety requirements for school buses.

Sorry though, for reasons I have already explained above, the suppression of marijuana cultivation and trade -- or attempted suppression if you wish -- requires a comprehensive scheme that penalizes even small scale cultivation or transfers.

[Know your rights]

None of that directly addresses my question, "how much of New Deal commerce clause abuse would they undo?" Based on what you've written, the answer appears to be "none." Sorry, but as a conservative I can't accept such thin gruel.

[tacticalogic]

Under my projected revival of dual federalism concepts, matters involving local police powers without an appreciable impact on federal commerce ought to be beyond the scope of the federal commerce clause.

Who gets to decide, and on what basis something has an "appreciable impact" on federal commerce? "Appreciable impact" doesn't seem to be any more than a re-hashing of "substantial effects". Under that doctrine, a majority of both houses of Congress, the President and 4 of 9 Supreme Court justices found that wife beating has a "substantial effect" on interstate commerce. One more liberal justice and the VAWA would have been upheld. What is this "appreciable impact" that they could not "find" that it meets that standard just as well?