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I guess the dictionary definition of the usage is the following:
どちらかというとその傾向であることをいう語。たぐい。 （＃4 精選版 日本国語大辞典）
So the sentences in the question literally mean:
Mr Sato, do you tend to be good at English?
This tends to be used often.
The usage may have derived from the original meaning of direction or side so that Xするほうだ can be understood as on the side of ...
1
There are good linked questions, but I think I'll try my hand at an answer.
There exist constructs and words in Japanese that either take on a different meaning, or can only be used with a negative sentence. しか is one such construct. It can only be used with a negative sentence. It is grammatically incorrect with a positive sentence.
For instance, ほとんど can ...
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