<<In the USA this is done to some extent as well, using limited remote communications outlets...which are very effective, providing good ATC communication at locations that would normally be out of contact.>>
Not sure that this is quite the same thing. In the UK we have multi-carrier transmitter/receivers, far remote from the ATC unit. Eg, for some London Control sectors the transmitters may be in west Wales or northern England but controlled from the centre on the south coast of England. This isn't the same beastie as the cross-coupling arrangement, although far remote multi-carrier stations may transmit cross-coupled frequencies.