[bawolff]

I think the article is just saying in practise its impossible to have entanglement on such a macro scale, so in practise the geiger counter would collapse the wave function and thus the cat would not stay in a superposition state. I don't see anything contradictory in that.

But its been a very long time and my physics is pretty rusty

[ithkuil]

Yes. In practice the cat, box, posion and Geiger counter system is not a fully closed system, and it gets entangled with the observer through unavoidable interactions.

When the observer's state gets entangled with the cat's state (whether gradually or suddenly) it's still perfectly valid to say that the cat is in a superposition of being dead and alive, and so is the observer in the superposition of observing the cat dead and observing the cat alive. That doesn't mean that the observer ever can nor should observe the cat being both dead and alive.

[lmm]

> I think the article is just saying in practise its impossible to have entanglement on such a macro scale

That much is not true though. Of course an ordinary cardboard box does not thoroughly isolate its inside from its outside, but complete isolation is possible in other situations (e.g. two spatially separated labs making measurements at the exact same time, which has been done in tests of the Bell inequalities).