What are the main limitations on using the following setup to boost frames per second capturing? Suppose I have two identical cameras, a red camera and a blue camera, that can both shoot videos at 1000 frames per second. If I set them up in the following set up, using a half-silvered mirror to capture the object highlighted in green, could I not technically achieve 2000 frames per second by simply overlapping the two sets of data I get from the red and the blue cameras? (e.g., take the first frame from the red camera, the second frame from the blue camera, and so on?) In effect I could double the frames per second of any camera with correct timing with the following set-up, though I've personally never touched a camera so I don't know the limitations that cameras could impose on realizing this dream of mine. I'm not too sure if this is off-topic either, sorry if it is.
You could get twice the frame rate if (big if) the taking times of the cameras were shifted by 1/2 millisec. In other words, the frame R1 is time stamped 0.0010 sec and the frame B1 is time stamped 0.0015 sec, and so on. Sync would have to be centrally driven, and registration would have to be perfect.

That leads to the problem that the frames from camera B would be horizontally reversed WRT the frames from camera R. This could be overcome, just something to consider when trying to register the images.