Answer:
Incisive... superflous.
Step-by-step explanation:
Semantically, trying to capture the meaning of the sentence in its context, the only options that make sense are the ones selected above. What the sentence is claiming is that someone wrote what could have been an incisive essay (that is to say, a critical, accurate, and poignant essay), had the writer not made the mistake to include certain superfluous phrases at the end of the essay (superfluous, meaning: unnecessary, superficial, and shallow remarks).