A President can pardon himself, thus falsifying the argument. And it’s the office of the President that matters, not the individual currently holding it. The person can be replaced. And until that happens, nothing prevents an indicted President from continuing to perform his Constitutional duties. Were you to argue that a sitting President can’t be jailed or imprisoned, you’d have a case. As it is, you don’t.
Not my words, not my argument, not my case.
It's the prevailing code that has survived a two-term Republican and two-term Democrat president.
In fact, were you to actually take the time to read it, you would find that the 2000 document merely aggregated the de jure Constitutional opinion of legal scholars - on both sides - going back to Nixon/Agnew.
As such, it has obtained the penumbra of law, as no contrary action has been taken, no criminal indictment made, in the 50 years since Nixon took his second oath of office; an era that includes a successful stress test of the Constitutional restraints as directed by the document: President William Jefferson Blythe Clinton III committing prima facie perjury in front of a grand jury.