Am i missing your point here but just because you have V sync on does not mean you will output 60 fps ?
3d Vision locks the graphics card output to the monitors refresh rate, it has to in order to work. The monitor will be running at 120hz with 60hz going to each eye, therefore the net effect is the game is locked to a maximum of 60hz.
The side effect of this is that if the graphics card cannot maintain 60fps to match the monitor, the framerate has to drop to the next available framerate that matches the monitor and that is 30fps. If you have a game that is hovering around 60 with frequent drops below that it will constantly fluctuate between 30fps and 60fps with nothing in between. (Looks awful.)
Triple buffering is ineffective as the graphics card has to double buffer in order to create one image per eye.

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