On Sat, 23 Aug 2008 00:22:21 +0100, John Rumm
wrote:

If you want switches on both sides of a wall, then chase one side only,
and run all the wires in that chase. Then drill though at the relevant
point for the other switch. (placing the switches slight offset from
each other)


Probably too late for the OP but if you just removed the plaster,
would this give you enough room to run capping on either side of the
wall without chasing?

The problem would be that if the light switches were back to back, you
would not be able to screw through the back of the box without hitting
the other! I don't know how you could get round this without making
one switch noticeably higher/lower/further from the door than the
other.