I used to skipper a big (50') cathedral hull american cruser thingy, like a floating american motorhome, with twin cummins diesels on 'V' drives, it had Mathers gear & throttle controls inside and on the flybridge, you just pushed a wee button at either station to take control from there (as long as the other station was in neutral and at idle).
They were ok, though there was a noticable delay in the gear shift actuation, which was a little annoying.
Quite a hefty servo arangement at each gearbox, operating the shift valve via a short (about 1 metre) morse cable.
I guess the main reasons for using the system were, very light control operation, whatever the distance tween control station and motors, and very simple dual station setup.
I believe the Mathers system is considered 'high end', they've certainly been around for years, this particular boat was mid to late eighties build. twoz called a mediterranean 500.
"I Agree with everything you say really!" - John Cooke to Jon Fuller - 26-01-2013