Sarcs
I note your reply, but a "general principle" is not legislation, and your quoted paragraph is unreferenced.
Your quote uses "SHOULD" rather than definitive terms such as SHALL" or "MUST".
A TAW/GPS warning in VFR conditions will be be treated quite differently in a practical sense than one received in IMC. Perhaps this difference may be reflected in the company manuals.
Not here to defend anybody, just can't see a blanket IFR/VFR rule.
Open to correction though.
Cheers