My main point was/is that it is not lunacy or impossible that it was staged.
"Lunacy" and "Impossible" are two different things.
Nobody has argued it would be "impossible" to stage a burglary, and even if it were impossible I'm not sure how you would prove it to be impossible.
On the other hand something can be possible, yet it could still be lunacy to believe it. 9/11
could have been staged by the CIA, just as the break-in associated with the murder of Meredith Kercher could have been staged by Amanda and Raffaele.
Evaluating such hypotheses is a matter of estimating how hard it would have been for them to stage it, how likely it is they would have staged it if they could, and how likely alternative hypotheses are.
This is part and parcel of the PIP meme that the police made up the staged idea to frame the kids. They say that there was absolutely nothing that should have had them consider staging. I don't agree. I've made a case that the most likely stager would have been Rudi himself if in fact it was staged. Why? Because the MO was similar to his and the kids could have just left the balcony door unlocked or the front door open.
I also believe that a rock was thrown from outside. It could have been by Rudi before or after the murder. He could have thrown the rock and then entered with Meredith as she showed up during his "waiting" period.
People under stress do weird things. However as has already been pointed out, the cost/benefit analysis of throwing a rock at a window
before a burglary to check for occupants or nosy neighbours when you are in a position to run away, is totally different from the cost/benefit analysis of throwing a rock at a window
after you have murdered someone inside the building and want that to remain undiscovered for as long as possible.
However I think we're still getting ahead of ourselves because we've still got no positive reason to think the burglary was staged. Sure, it's a theoretical possibility, but there are an infinite number of theoretical possibilities we don't bother to explore because there's no reason to believe them. Why are we focusing on this one?
The refrain that there was no evidence of staging of course is specious because as you noted a staged break-in would not need to be detectable. I would say Raf's response that nothing was taken, which proved to be true was highly suspicious.
It's not specious at all.
The police claim that there was evidence of staging. They make this claim as part of a network of claims that implicate and Amanda and Raffaele. Pro-guilt posters repeat these claims.
Repeating that there was no evidence of staging cannot be specious unless and until people stop claiming that there
was evidence of staging.
Also, since an undetectable staging effort is highly improbable, it's only got a legitimate reason for existing as part of this conversation
if and only if it is a necessary part of a larger, compelling narrative. Show me a narrative of the crime that explains everything much better than the generally accepted pro-innocence narrative and which requires an undetectably staged break-in and I'll be interested. Until then, we might as well postulate a narrative where undetectable leprechauns did it.