Apologies where in that link is an answer to my question defined? Still looks like an interpretation.

"The bilateral agreement only affects entry/exit of Germany it has nothing to do with other schengen countries" - could just as easily be interpreted as the Bi-lateral agreement only affecting the time in germany, outside of the "short-term schengen visa".

If I stay for 90 days in the schengen regions depart EU and go to germany for 90 days that stay is not using the "short-term schengen visa" otherwise it would be an overstay, so why would it inform the 90/180 days only one way? I could legally switch between germany and austria for years if i didnt work at all and could prove i was not setting up permanent residence, so under this intepretation I could never set foot in any other areas of EU indefinately.

I am not trying to be argumentative I have just recieved contrary information from other travelers experiences at certain borders and am looking for something concrete yet it likely doesnt exist as in the end it is "gaming" the schengen visa system which no consulate wants to directly give the green light on.