unattributed "reviews"

When a "review" is unattributed, can I assume that it's written as just a descriptive blurb?  Generally, descriptive blurbs are descriptions that can be gleaned from the liner notes and press junkets.  They don't go into depth about any song, except maybe to mention one was a single.

However, the unattributed review for Mutual Admiration Society seems to be more than a descriptive blurb.  It opines about the songwriting and aesthetic style; comments on the album's "tone and atmosphere"; and concludes that the album is a "quiet, thoughtful collection".  It also doesn't contain any negative critique to justify a rating less than 5-stars.