It just seems like habits make their way through this space without evidence, and back their way into being established as canon. Like the careful way we are "supposed" to reconstitute peptides, when Janoshik shakes every single vial vigorously. Also (as said by Janoshik) the myth of the dangers of HGH denaturation because of temperature variations in transit (valid with liquid perhaps, but nearly never in lyophilized vials).
So while the risk on peptide mixing increases depending on environmental factors, and to a lesser degree potential PH conflicts, it still seems very dependent on how the vial is stored and treated post-reconstitution. Add that to the duration of its use and we have a best guess that we probably want to use it within the month of reconstitution, but we are not provably wasting our time by buying and using KLOW vs four separate vials that require four separate injections spaced out in far enough intervals to avoid the internal mixing risk curve.