I have a bicycle with stem mounted friction shifters, and I really like the way they work. I would like to use a similar friction shifter on another bike, but that bike has a threadless headset and the shift levers can't be mounted there. I have considered bar end shifters, but the bike has flat bars. I also considered thumb shifters, and like the idea of being able to access the shifter and brake lever in the same position. But friction thumb shifters all seem to be designed to be mounted on top of the handlebar, above the brake lever. This seems less ergonomic and intuitive than mounting below the bar and lever, where the lever can be accessed without changing hand position, similar to how trigger shifters are typically designed.
My question: has anyone experimented with mounting normal top mount friction shifters below the bar, or found a different way to achieve the same effect?