Juan de Mariana - The Anarcho-Monarchist Visionary?

The great Jesuit Juan de Mariana is that man who most anarcho-libertarians know for his unprecedented understanding of the economic theory of money and principled stand against tyranny of any kind. But isn't what Mariana describes in some way a proto-Anarcho-Monarchist order? I would suggest so. Coming from the traditional Monarchist tradition of the Catholic Scholastics, Mariana writes about the people freely aiding the King while he performs his duties of protecting them and their property. He also points out, however (in his De Rege), that all people have to consent voluntarily and any authority gained by conquest can never become legitimate - even if the conquered party consents to the ruler (or state legislation) after the fact. Furthermore, if any subject of the King deems that the King is not acting in society's interest, he may freely leave the jurisdiction of the King by secession (Mariana does not explicitly say this, but I infer it from his writings about any party being able to break out of the 'compact' when wronged). And, if the King prevents him or a multitude of others from doing so while acting in a tyrannical way (imposing taxes upon them without consents or not allowing them to voice their opinions), he may justly assassinate the Tyrant. There is the key difference between Kings and Tyrants that Mariana points out and John Locke also mentions. As Locke writes: "[U]surpation is the exercise of power which another hath a right to, so tyranny is the exercise of power beyond right, which nobody can have a right to..." Clearly Tyrants and/or usurpers may be assassinated and this is justified by simple self-defense.
Mariana gives the example of the famous French monk, turned assassin, Jacques Clement. Brother Clement was justified in killing French King Henry III because the latter had become a tyrant and was no longer worthy of ruling the nation. Henry assassinated his Catholic opponents and tried to support his rule (and his successor's rule) with force.
This is, of course, not what Anarcho-Monarchism is in an exact degree (in my opinion, at least). Mariana, though an individualist Scholastic, still held some superstitious beliefs regarding the nation and the state being a single 'body politic' with a will. The breakthrough he reached was actually the limiting of this general will's power to a very large degree - but he never really dismissed it entirely. An Anarcho-Monarchist society would be even more voluntaryist and individualist than Mariana's. This is because Mariana's society relied mostly on personal honour, honesty, and chivalry. Such virtues are always laudable, but it is also always good to prop them up with contracts. Good will is not always enough to win the day.

So, was this rebellious Catholic School-man a predecessor of the Anarcho-Monarchist movement, and can his doctrine help define ours? You decide.