Secondly, I suppose human eyes focus on circular areas, instead of horizontal lines. That is, the very focal point is a round dot, the farther away from it, the less focus; eyes do not focus on one fixed-width line, the farther away above or below or to the left or right to it, the less focus. Chinese characters have the advantage of packing semantic information in a square block, compared to English which spreads the same information out horizontally, whose acquisition requires left-to-right scan by the eyes.
The Korean language is a unique case in that its letters are arranged both in a block and horizontally. It's a perfect compromise between English and Chinese. The eyes can gain some information focusing on one spot but usually must move horizontally to gain enough for a word. So the reading by the same person reading the same content will have the intermediate speed.
On the other hand, a March 24, 2015 article reports the research by Georgetown University scientists, After learning new words, brain sees them as pictures (probably based on this publication). Indeed, our brain does not process English text strictly linearly when our eyes horizontally scan the line into our brain. This means that the distinction between a language with largely block-based information (Chinese) and one with line-based information (English etc.) is not so dramatic. Nevertheless, I would be very delighted if we could find a person perfectly trilingual in English, Korean and Chinese, or at least perfectly bilingual in two of the three, to test his reading speed. Personally I'm not sure if I'm perfectly bilingual in English and Chinese. But I do feel that my reading speed in Chinese slightly better than in English. But I have not done a well-prepared test.[note2]
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[note1] He's said to be a maximal trilingual, in the field of Second Language Acquisition.
[note2] Obviously the test must be given by another person. Since the person taking the test naturally reads the passage faster if he's already read the same content in any language, the passage actually cannot contain the same content translated into different languages in real implementation of this test. How the test can be given in the most appropriate way may be a technical challenge.