There's a hole in your argument that I can drive a truck through, and that hole was made by the use of the word "arbitrary." You act as if Colson is saying the president may reject a SCOTUS ruling if they say toe-may-toe and he says toe-mah-toe. But "arbitrary" is hardly the issue.
For example, Lincoln defied the SCOTUS because they had overridden the clear intent of Congress on a very thorny issue that had been passed after decades of debate. Moreover, the Congress had passed the Missouri Compromise in an effort to save the Union, and the SCOTUS was undermining that just to make sure dipstick slave owners didn't have to worry about losing their "property."
You seem to be missing that we're talking about a situation where the SCOTUS defies the Constitution and the clear will of the people, and does so in a way that endangers the Republic. That's hardly an "arbitrary" situation, and it is a situation where the POTUS and Congress must act to preserve good order and separation of powers.
I considered using a different word but finally came back to arbitrary which means subject to individual discretion or preference. If Colson's proposal were the custom, I think the President's constitutional reasoning would be no better that the Court's for which arbitrary is a good description. They adhere to principle only when convenient for their desired result. When it's not we get penumbras and emanations and reversed decade old precedents. Presidents would do no better, in fact they'd probably be worse, being subject as they are to influential lobbies and passing political pressures.