I have great respect for Thom Hartman. In this instance, I would suggest a slightly different variation on this
..it is still an incomplete coup, in process. I'd compare the op-ed to the messages that the military generals were sending to the US in the summer and early fall of 1963, saying they were prepared to remove Diem from office if they got the okay signal. That was part of a coup in process.
If we took the worst parts of Diem's personality, and combined it with his brother's ruthless brutality and sister-in-law's evil, we can see how these generals came to their decision to remove the sociopathic leadership. Yet, within the military, there were plenty of soldiers willing to follow that leadership. And that coup, once completed, created a vacuum that allowed for various other terrible factions to gain power.
As you point out, our Constitution allows for the orderly removal of a president. There are two options found there. It is curious that anyone would hold that following the Constitution would create a "constitutional crisis." A rational person might conclude that failing to follow the Constitution can only result in crises.
And yes, Woodward knows who submitted the op-ed. The Times editors needed five days to clear it in advance of its being released, and it was agreed it would run the day after the Washington Post released the bits from Woodward's book.