So, this theoretical perfect time measurement won't work on or near any planet or other massive body (where "near" is relative and as your technology improves i

So, this theoretical perfect time measurement won't work on or near any planet or other massive body (where "near" is relative and as your technology improves it will get bigger and "massive" is relative and as your technology improves it will get smaller). It also won't work in any accelerating frame of reference, such as spin-gravity. So, this is "possible" only in the sense that if constrained to be useless it would theoretically be possible, but not practical. Awesome, let's get right on that :-)