Sentence:  Final blow to the reviewer's smarting eyes and ears were the parting shots in which (1) a whole group was <WSD>scanced</WSD> with its back to the audience while doing what must have been intended to be a satire on a community sing, and (2) Peter Donald did a closing announcement in which the choral group completely drowned out his words. 
Meaning of the word marked with <WSD> tags:  (Scottish) To give a cursory examination.