So you're saying that, effectively, anything that Joe Public can request an adversary can request, so that by giving Joe Public access to the database you'd be giving an adversary the same access?
No. You're over-simplifying what I said and arriving at a trivial statement. I suppose I would correct your summary to be "The mechanics of current homomorphic encryption mean that by giving Joe Public _ONE_KIND_ of access to the database you'd be giving an adversary _ANOTHER_, _MORE_POWERFUL_ kind of access to the same database."
I'm responding to the GP, who was hoping that homomorphic encryption would allow TPB to hand an attacker a working copy of the database on which the attacker could run queries, but not leak information about what the database was doing.
I'm making the statement that allowing Joe Public the ability to interpret query results allows the attacker the ability to observe the database's internal state at each step of the query, nullifying any advantages of homomorphic encryption.
I explained why current homomorphic encryption doesn't allow the kind of separation of access the GP was hoping for, and outlined one way a theoretical discovery advancing the state of the art might allow what the GP was hoping for.
I'm responding to the GP, who was hoping that homomorphic encryption would allow TPB to hand an attacker a working copy of the database on which the attacker could run queries, but not leak information about what the database was doing.
I'm making the statement that allowing Joe Public the ability to interpret query results allows the attacker the ability to observe the database's internal state at each step of the query, nullifying any advantages of homomorphic encryption.
I explained why current homomorphic encryption doesn't allow the kind of separation of access the GP was hoping for, and outlined one way a theoretical discovery advancing the state of the art might allow what the GP was hoping for.