I'm having a new bathroom fitted with an over the bath shower (thermostatic
mixer valve) and want to tile the walls and floor. As I've had problems in
the past with the seal between the bath and the tiles, I've been told to fit
the bath first and then tile the walls so that the tiles are resting on the
bath edge, that way if the sealant ever fails the water from the shower will
(hopefully) not drip out of the bath and into the floor below. I've also
been told that to make the tiling easier and to avoid having to fit tiles
around awkward shapes like the WC, I should fit all the pipework, then I
should tile the walls and floor (tiling around the pipes sticking out of the
wall) and then I should fit the WC, sink, shower and shower screen. I'm
intending therefore to fit the bathroom in this order:

1) Fit bath
2) Fit pipework for WC, sink and shower.
3) Tile walls and floor
4) Fit WC, and cistern, sink, shower and shower screen.

As this is my first bathroom can anyone offer advice, is this the best order
to fit everything?