Some folks have said he is better at deposition than one might expect. But I am sure his behaviour generally would terrify his attorneys about what he might say.
For myself, I think he is attempting to discredit and shut down the probe before the deposition.
We shall see whether he succeeds.
I like the final line: the value of charging Trump would be to remind folks that no one is above the law. That is a simple expression of what the rule of law means. Out of the same argument, Magna Carta was written. Trump is America's King John.
One thing is incredible to me. That the entire US Constitutional system doesn't provide more protection for this central plank. It is extraordinary to me that the President is actually empowered to disrupt the investigation.
I suppose the reason they haven't put such protections in place under Trump is because they are concerned by the potential impact of the optics of doing so. Hopefully behind the scenes they show more strength.