I believe it is recommended to use one relative layout instead of multiple linear layouts, because depth quickly becomes slower than the more complex measurements needed for a relative layout.
I find layouting on Android really bad TBH and there are so many presentations and guidelines on what (not) to do.
Its hardly more performant. But here is some more info: https://www.youtube.com/watch?v=NYtB6mlu7vA&t=1m41s
Yes, the documentation is far from good.
But the larger problem I find is that the 2 platforms are made from opposites points, and I don't see Xamarin glueing it together as magic.
But you are right, the layouts and measurements even differ per api level as they get optimisations and are really complex. It would be awesome if Xamarin could combine both platforms native performs, but I don't see that happening :(
