I'd like to know whether it's okay to reveal the identity of a person in advance when having others judge his or her sentences for grammaticality. Will that affect the reliability of the judgments? If so, how do we avoid it? I'm talking about having people judge the grammaticality of written sentences.
If the question is whether speaker name influences listener reaction, you should include the speaker's name (otherwise you can't test the hypothesis). For instance if you had marginal utterances read by a speaker identified with a typical name in the language, the probability is greater that listeners will judge the utterances as grammatical, compared to if the name is extremely foreign (people will impute language incompetence to apparently-foreign people). There isn't any good reason to reveal a speaker's identity in a perception test, unless the speaker's identity is an effect that you're investigating.
I wish your question were more detailed. Is it about written or spoken sentences? Is it about the person who reads the sentence or who made it up? Anyhow, I'll give you an example when names do matter.
In languages with prescriptive grammar, like Russian, the norm has changed since the 19th century, that is, what is considered wrong grammar or wrong word usage nowadays was normal and correct back in the 1800s. It's a typical situation on the Internet when people see a sentence which is ungrammatical from the point of view of the Modern Standard Russian grammar, they all start pointing to the mistake and correcting it, but when thy learn it's a quote from a famous Russian 19th century writer, like Pushkin, Tolstoy, or Dostoevsky, they get silent at once. There are two reasons for that: firstly, the mere authority of those names makes every single sentence they wrote grammatically correct, since it was actually they who established the grammatical norm of the Russian language. And secondly, although many are well aware of the current norm, few know what norm was there in the 19th century.
That example is to illustrate how revealing the name can change attitude towards the grammaticality of a sentence. Depending on what those judges will investigate, the names can be revealed or concealed, but in any case the name can really mean much.