The story (urban myth?) I heard was that while Giovanni Gola himself was responsible for the instrument lines, he (or whoever did the actual work under his purview) used 3 complete a mano sets of reeds to pick best matching and responding reeds for each instrument he signed off on.The Hohner Morino M series comes in to versions: an older version with Artiste reeds on the treble side (and inferior reeds on the bass side) and a later version with Bugari tipo a mano reeds. Everyone I know who knows that these two versions exist told me and others that when looking for a Morino M (for instance the most popular, the IV M) to look specifically for one with the Bugari reeds. I have worked on both and I must agree: the Bugari tipo a mano reeds are better than the Hohner Artiste (hand made) reeds. Hohner probably cherry-picked the best ones from whole series that were made to put in the Gola.
If that story holds water to at least some degree, that would result in a number of (less consistent) a mano reeds to be employed in other instruments. In that case, I'd expect a hard cut-off date on those "some lesser instruments have surprisingly good reeds" effect like seen with the Bugari Atlantic de luxe instruments: stopping that cherry-picking is a very obvious way to save a lot of money on quite diminishing returns and would probably have ceased within a year of Gola keeping tabs on the production (as opposed to Morino, I think he returned to Italy after being pensioned and so there would be rather little grace period before checking what practices to leave in place and what corners to cut).