That's quite unusual I would say.
It has a few problems, too. One of the biggest is that you can't close window sides independently. Take a close look on how the window latch operates. Do you still want to defend that position ?
Is there some reason you couldn't hold the window in place with one hand (or have an accomplice do that) while you leaned out and chucked a rock at it with the other? It seems like a pretty dumb thing to do, with obvious risk of injury to the people doing it, but people have done stupider things.
Mind you, the Massei theory is that Amanda and Raffaele broke the window by throwing a rock
out the window with the shutters closed to catch it, and then putting the rock down in the room. That's his story for why there is a pile of large pieces of glass directly outside the hole on the sill, but none on the ground below. Of course, Hendry's thesis that Rudy removed those pieces of glass from the frame manually and put them there also explains this, along with explaining much better the spray of glass
into the room, which Massei's theory simply doesn't account for properly.
Massei's story on that point is this:
Massei said:
As for the presence of glass in Romanelli's room, the violence of the blow, the characteristics of the glass (which was rather thin as indicated by Romanelli and Pasquali), the large rock used, and finally the shield effect caused by the inner shutter hanging half-open behind the glass pane [41] (a position of the inner shutter which corresponds to the scratch on it visible in the photos) give an adequate explanation of the distribution of the glass.
In other words it was a big rock and they threw it really hard, so glass went backwards all over the room. That seems counterintuitive, to put it mildly.
Whereas the thesis that glass went all over the room because Rudy threw a big rock quite hard from
outside, and the pile of glass outside the hole was put there manually by Rudy as he widened the opening, explains the distribution of glass far more intuitively.
So even if a staged break-in is
possible using the Quadraginta backwards throw theory (or indeed the equally meritorious "they just went outside and chucked a rock through their window" theory) that doesn't really amount to much. The Massei story about why he thought there was a staged break-in in the first place doesn't stand much examination, and without a reason to believe the break-in was staged postulating a staged break-in is definitely multiplying entities beyond necessity.