I do thank you all (the nicer ones, especially) for replying, despite the fact that the responses mostly did not deal with the initial question, posed at the top of my original post, which I will restate in a slightly rephrased form here:
Can FCP allow you to capture (ANY amount, or as much as) up to 2 full terabytes of live camera feed without stopping, by somehow breaking the material into smaller individual clips AS IT CAPTURES?
(Probably I was distracting from that question, partly by describing the sheer folly of my first attempt, admittedly a fairly silly effort. But, for those who are still wondering, this is about finding a way to fully document a NON-STOP event (a world record attempt with absolutely no breaks) for about 3 plus days, with as few as ONE camera and ONE computer.
BUT back to the main question, further rephrased: why shouldn’t there be a function of FCP that would allow the capture process to continue at great length (even if unmonitored or unattended by the user) by automatically breaking up the capture into shorter clips without requiring any manual stopping or restarting of the capture process?
Thank you again in advance for any helpful ideas or suggestions.