"For all practical purposes" is not a constitutional term. The only way to repeal any constitutional statute is to amend the Constitution with an express repeal of that statute.
I recall justice Scalia at a chitchat with a congressional committee within the last year. He rattled off a bunch of swell sounding rights from the constitution of the Soviet Union. The problem was that the government, people, everyone ignored them and they were never in force.
The point of Mark's book is to reestablish what we have lost, to restore the American Republic.