Answer:
It is not concrete nor constructive.
Step-by-step explanation:
Peer review feedback should always aim at an honest, and as much as possible, cordial, critique of somebody´s work. Feedback should always be precise, that is to say, it should signal where exactly flaws are found; also, it should be constructive, not destructive, that is to say, it should give the author arguments on why certain fragments are flawed and give the author tools to fix these flaws.