I'm looking at it the other way
The tester has measured and recorded R1+R2 and added it quite legitimately to the also measured Ze.
He comes up with a perfect Zs,whereas the op thinks that measured Zs is dodgy (because he thinks R1+R2 and adding Ze is a calculated reading)
I'm now getting flummoxed by what is being suggested
I think the op needs to expand on what he thinks is actually being fudged
The tester has measured and recorded R1+R2 and added it quite legitimately to the also measured Ze.
He comes up with a perfect Zs,whereas the op thinks that measured Zs is dodgy (because he thinks R1+R2 and adding Ze is a calculated reading)
I'm now getting flummoxed by what is being suggested
I think the op needs to expand on what he thinks is actually being fudged