True. But as I said, it is untested. And it has worked so far.
The Military, Police, courts, civil service etc all pledge allegiance to the King, but it's Parliament that fund them. To me, that's a great way to stop coups. How would a coup even happen in such a situation?
The US though, they swear to the Constitution. And as we have seen with Trump, he appears to consider himself above the Constitution. There has been, and is, a real worry about a coup with Trump. Jan 6th, it really was a thing that if the National Guard had been called out, who would they have supported.
Our system makes us a coup free zone. Could anyone honestly say the same about the USA ?
That's my logic anyway.