The difference between moving money in your situation and in Apple's, where there's no correspondence between where engineers are located and where IP is licensed from.
By forcing all revenue to go through a single point (the headquarters) it's much harder to establish fake licensing like Apple Ireland's.
Ok, I was commenting on the US subsidiary of Canadian firm example (which you didn't seem to agree on).
But I don't think that the meaning of "forcing all revenue to go through a single point" is clear at all.
From the point of view of most countries sending money out to Cupertino wouldn't be an improvement over sending it to Cork if that still means that they don't get to tax it.
By forcing all revenue to go through a single point (the headquarters) it's much harder to establish fake licensing like Apple Ireland's.