[xelasnave]

Thanks Bojan.
I don't like to think about SR and GR as when I do I feel there is something wrong that I can't nail down.
GR not so much but SR...mmm how can I put it...the clock ticks away at whatever rate..but the observer see it differently...it would seem the actual tick rate is one thing ..that is real but the observation is a perversion of the reality..damn it it is like trying to hold an eel...so I feel that any adjustments for SR must be at the observer's end..ie don't touch the clock being observed...whereas for GR the position is probably the reverse..but I am worn out think about SR..I mean thinking about it rather than merely accepting the premises we are told.
There is something I can't put my finger on...the reality...tick rate..And the illusion..the observed tick rate....the observer is seeing a mirage maybe.
The second part of the link I provided makes a claim that the subjected input or lack thereof of SR and GR is nothing like that claimed. I wonder if that claim is valid as I become suspicious of any side that makes exaggerated claims..someone is telling pork pies...how do we work out what nano seconds translate to in terms of error... just be easy math... who is fibbing... the guy who wrote the article or the advocates of SR and GR s importance to GPS.
How do we work out what one nano second error does to position.

Alex