Sure, just like the relativistic effects of GPS clocks on Earth are predictable. But it makes clock keeping on Mars much more complicated, always making correct

Sure, just like the relativistic effects of GPS clocks on Earth are predictable. But it makes clock keeping on Mars much more complicated, always making corrections. The corrections are always changing and syncing time is hard because the motions are always changing. Simplest solution is to use local atomic clocks. And then calculate Earth time when needed. All for zero benefit because the Earth is variable number of minutes from Mars so there will always be variation. Mars day is different from Earth have to calculate Earth time anyway.