I tend to be skeptical about extraordinary claims of speed reading.
I left some thoughts about the claim of reading 25,000 words per minute above. 25,000 wpm is impossible unless there are tricks involved, like reading the same word written 25,000 times in a row or magic. Taken at face value 25,000 words per minute is more than 416 word per second, which is physically impossible.
Nodas wrote a good post about speed reading competitions where there are rules and experienced judges to verify things. I think that gives a more realistic picture about what is possible. I’d be skeptical of any claims that go too far beyond what has been performed in front of judges.