This is just sort of a open ended question, I am curious to see what people think...I was just reading the "42 H&H wide" thread in the builders forum, which turned into a debate on the pros and cons of trolling valves. It got me thinking ( I know, dangerous!) - why is it that the trolling valve seems to be the only widely accepted means of slowing down the hull speed at idle for boats with big diesel power? It just seems kinda low tech to use what basically amounts to clutch packs that you can lock up to run at speed or allow to slip to reduce prop Rpms at idle ( assuming my understanding of how trolling valves work is correct). Maybe there is a really good reason and I am just missing it, but why don't these boats use 2-speed transmissions to do the same thing? You could run on low gear (which would have a very high reduction) to slow the prop down for operating at low hull speeds for trolling, docking, etc, and then you could use the high gear, with your typical reduction for operating at higher speeds... I don't know, seems simple, but I'm sure there's a reason it's not, or boats would be set up that way. Just curious what people think or if people have seen it done.