I took Patrice's post to mean that the results of that study did not indicate that the adults in it had learned
perfect (or ... absolute

) pitch. Which is different from saying that perfect pitch can't be learned - Beato's point in the initial video, for instance claims pretty defiitively that perfect pitch IS a learned thing ... it's just that it's learned very young, and basically subconsciously (like one's native language). He does in the later video here featuring his son, talk about degrees of perfect pitch - Dylan is clearly on the upper end of that scale. Wow, impressive ability.
Looking at it through the lens of longfinger's post, perhaps there are two different things that both (often) get lumped together under the single name "perfect pitch". One, "Perceptual Transcoding" is what Beato refers to as "perfect pitch", and does seem to be ... perfect, generally. The other, "Heightened Tonal Memory", is something that in Beato's description might not be classed as "perfect pitch" (i.e. may be less "perfect" and less instantaneous), but still can give results that are somewhat similar (Amy Nolan appears to have that heightened tonal memory, naming any note that's played on the keyboard ... but not unfailingly generating any note (vocally) independently of any reference point or instrument.
Maybe it is indeed then, in part, a matter of semantics ...