If there are sockets in sufficient positions for all round house
access then this would make it most unlikely that an internal
socket was used for external appliances, therefore to my reading
of the regs you would not have to protect the internal sockets.

On the other hand, I wouldn't dream of not protecting the inside sockets. I
think the regs should be changed to mandate the protection of inside
sockets, except in special circumstances (i.e. non domestic situations).
However, I agree that waterproof outside sockets should be provided with
independent RCD protection, as well.

Christian.