Setting papersize in reference cards

Hi,

Please see

  https://sourceware.org/pipermail/gdb-patches/2025-August/219754.html

where Vincent proposed a patch for the GDB refcard, and the following
discussion, which indicates the problem is not just in GDB.

Could someone here please help us understand:

 . why is this setting needed
 . what is the default setting for papersize for the DVI output
 . is the proposed change TRT, or could it cause some problems in some
   locales
 . is something like that needed for every TeX document that is
   supposed to support generation of DVI
 . how come generation of PDF output doesn't need this setting

I post these questions here in the hope that the TeX expertise on this
forum will allow us to understand the issue and make correct decisions
about any changes that need to be done.

TIA

P.S. Please CC both me and Vincent on your responses, as we do not
subscribe to this list.

P.P.S Apologies if this is the wrong forum; if so, please suggest
where to post these questions.