In the case of your example with
superb, I think you are using what are sometimes called
scare quotes. They can be paraphrased by preceding the word with
so-called.
That is, they show that the author does not really believe what he's
quoting. He is implying that less informed people might believe
it. Or, in less extreme examples, the author is merely drawing
attention to the fact that many people use the word, and perhaps
incorrectly or in an exaggerated way.
John is a superb actor says that John's acting is excellent.
John is a 'superb' actor says that he is a so-called superb
actor, that is, he is regarded as superb by some, but they are probably
wrong in the opinion of the author. This is totally a written
effect; there is no easy way to phrase it with your voice if you
actually say it. (The sentence is actually not the best example
of this kind of usage.)
I don't see any reason to use scare quotes on feedback in your other example.
(I
have no idea if this is the use of quotation marks referred to earlier
by Mr. M. The two of us may be referring to two completely
separate stylistic phenomena.)
CJ