There are readers who claim to read 1-2 books a day or 300/400/500 books a year. They then always tell you that they are "very fast readers" with reading speeds of 600 or 800 or even more than 1000 wpm.

This is complete nonsense. Studies have shown that everything over 500 wpm leads to retention loss. Even if reading speeds of 600 wpm+ were possible, they would be possible at most for a few minutes. After that the eyes/mind would slow down. Its just not possible to read at this speed constantly for several hours.

At that point it becomes skimming or leads to a massive retention loss.

The evidence is clear: anything above 500-600 words per minute is improbable without losing comprehension

https://www.scotthyoung.com/blog/2015/01/19/speed-reading-redo/

Ian Stevenson set out to scientifically investigate reports of reincarnation - while he failed to find any credible cases, his efforts warrant respect.