I agree with you but if you read carefully, it says that distraction does not affect validity of the exam. Moreover, it says that mothods of detecting distraction are effective and ETS will try to reduce noise level. It does not say that it will get rid of the distraction. It is called, "Sugar Coat" as you say.
How can ETS control environment when a majority of test centers are not standardized? Sources of noises started from test proctors listening to music on the computer without headphones, discussion of passport problems with other test takers, shouting of other test takers who have loud voices, to the echoes of microphones.
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