Quick Question regarding HiPot testing and V +\-

hello all,
I work in a test lab and have a simple question that is burning some people up and just want to make sure that my understanding is correct (or NOT!)
We must leak test between open contacts, lets say A and B at +18kVDC then reverse leads and test again (B to A). later we must test -18kVDC between same open contacts A to B then B to A.
I am being told that by switching the leads (pos lead to A ; return lead to B then return lead to A ; pos to B) we are satisfying the + and - 18kVDC requirement.
I do not believe this to be true. We are simply changing the electron flow through A and B. This does not magically change the source current to a symmetric but opposite signal.

It would be super cool to get some insight on this whether Im correct or not.

BTW I could proooolly get fired for posting this question online =D
Cheers ahead of time!

How do you currently test with -18kVDC?

It seems like you are doing two redundant tests. The sign of the voltage is only meaningful relative to a reference point, if you swap voltmeter leads, then the sign of the voltage on the meter changes.

You can probably prove this to yourself if you can put your Hi Pot on a low enough setting that your voltmeter can handle it and test the voltage in each configuration.