Thanks for everyone's comments.
now I think that any national standards would not be helpful for this case.
Basically the drawing scale on a reduced size print is not matched with any standard scales and no one can tell the true drawing scale on the reduced size print.
Not us, but our client(s).
This is my concern.
I think this is horrible splitting one drawing to two small sheets when it was possible fitting in a single A0 or A1 sheet.
Again, by using reduced size the CAD drawing scale is meaningless.
We normally set the drawing to a standard scale (ie. 1:50, 1:100, 1:200 ...).
Now everyone can start a drawing with a scale of 1:37.5, 1:85, 1:136, 1:578 or simply whatever they want because of trying to fit models in one small sheet.
The CAD drawing setup then would make no sense at all.
Furthermore, the details drawn would be just wasting the drafters' time because no one can read the details on a reduced size print.
Am I right?