Trump has very strong principles. They are almost universally aligned with my own. He is unparalleled as both a leader and a policy maker.
But he does make predictions that will never come to pass. Sending in the Army to settle things in Seattle is just the latest example. It’s not a deal killer but it is an avoidable error. Trump is too smart to make a mistake like that and actually do it.
Making a prediction that he won’t watch the NFL if they allow kneeling is hardly analogous to sending the army into Seattle. You can’t say you believe he is principled and at the same time say that he won’t keep such an easy promise. I think you’re confused.