The "King of Nemi": how long does it take the penny to drop?

I am about to go off to Italy (on a recce for a possible tv programme, and for more honourable reasons). And I have been thinking about the about the story of the Rex Nemorensis, which memorably starts Frazer's Golden Bough. This was the priest of Diana at Nemi (just outside Rome, nicely imaged above) whose succession was distinctively violent. You could only become the priest of Diana at that particular site if you killed the previous incumbent.

The story was that Caligula (the "mad" emperor Gaius) insisted on a change of regime at Nemi, and hired an adversry to unseat the reigning king. And this was what Frazer had fixed onto in thinking about the primitive divine kingship with which he was so preoccupied.

But isnt there another way of seeing this?

One of the things that Walter Scheidel, among others, has recently stressed is the pattern of violent succession in the transmission of imperial power: most of them either were, or were alleged to have been, murdered. There was never so violent an image of succession as you find in Rome.

So how do we understand Caligula's reported intervention in the succession of the Rex Nemorensis? Frazer had one rather mystical view. But it has just struck me far too late (how long DOES it take for the penny to drop?) that the Rex Nemorensis was at root a metaphor for Roman imperial power itself (the rex of the Romam empire that would never call himself such, but kill your predecessar was the basic rule).

What Caligula was saying was that the transmission of power between reges was alway necessarily bloody.. and the joke about the Rex Nemorensis as always already about imperial power in general: kill the bugger.

I guess that someone else has seen this before, but I had been dumb and hadn't.