lack of common definition for "ZKP" in a VC context

I've had several interactions recently, including one just today at RWOT,
that lead me to believe our community has divergent definitions of "ZKP" --
or at least we are applying "ZKP" in a credential context in fairly
different ways.

I won't argue the virtue or lack of virtue of ZKPs with credentials, and
I'm also not trying to convince other ZKP proponents to adopt my
definition, but I do want to at least formally share how Hyperledger/Sovrin
uses that term, so we are not mischaracterized. If there are other ZKP
voices in this group that want to chime in with their own definitions, that
would be useful.

In Hyperledger/Sovrin parlance, a ZKP is not a synonym for a presentation
that involves predicates; nor is it a synonym for a presentation that uses
CL signatures. Its defining characteristic--the "zeroness"--is how much
extra knowledge is leaked. If you leak zero knowledge beyond what the proof
request demands, then you have achieved zeroness. If you leak any knowledge
other than what the proof request demands, you have not. This is in the
spirit of the inventors of ZKPs, whose seminal paper says:

Zero-knowledge proofs are defined as those proofs that convey no additional
knowledge other than the correctness of the proposition in question. (S.
GOLDWASSER, S. MICALI, AND C. RACKOFF, The knowledge complexity of
interactive proof-systems, SIAM J. Comput., 18 (1989), pp. 186-208)

Note that the wikipedia article on this topic, as well as many online
tutorials, vary in whether they use this definition, or a narrower and more
recently prominent one that suits their own contexts. Thus, not everything
that you can read about ZKPs on StackOverflow or various crypto blogs is
actually describing the same ZKP concept as Hyperledger/Sovrin. I'm not
saying anybody is right or wrong--just pointing out differences.

While it is true that Hyperledger/Sovrin implementations of ZKP credentials
support predicates (aka "zero knowledge proof *of knowledge*"), I expect
most ZKP-based presentations to disclose things as well ("zero knowledge
proof of *<a value>*"). For example, if you intend to ask Alice to disclose
her first name and city of residence, you can do this in a ZKP way. You
don't do this via predicates; you actually say the machine-readable
equivalent of "please prove the actual values of firstName and
cityOfResidence".

You might say, "Well, what's the difference between ZKPs and selective
disclosure in that case? Why would you call that a ZKP?" And my answer
would be: *the ZKP that discloses 2 attributes differs from the non-ZKP
that discloses the same 2 attributes in whether a signature is disclosed.*
A ZKP discloses 2 attributes and 0 signatures (even though the credential
behind it has a signature over each individual attribute); a non-ZKP
discloses 2 attributes and 1 signature (or 2 if it supports per-attribute
signatures).

I'm curious to know if I'm being pedantic and redundant here, or if I
raised people's eyebrows.

--Daniel