I picked up one variant independently from reading Robert Jordan; I can only caution against it based on my experiences. I discovered after I started listening to audiobooks on long drives that I was missing large chunks of (only usually trivial) detail. It's taken several years to unlearn the habit.

Personal experience with speed reading "techniques" seems to indicate that their effectiveness largely depends on your skill, past experience, the topic you're reading about, how much you master the topic and how much of it you really need to understand / remember.

When I tried practical applications, what usually works the most is simple pattern-recognition of complete sentences as "single words", with the rest of your brain filtering through the less-useful words and adjectives and so on, which is extremely reliant on reading a lot of similar text. Then you can, in practice, eliminate most of most sentences, reading each sentence as a word and going through a paragraph like it was one sentence, relying heavily on intuitive/subconscious pattern-recognition and then flowing backwards to "fill in the blanks" of phrase complements, particular subjects, etc.

Basically, from my experience, speed reading is martial arts for reading. There's no secret technique, just lots of training and purging inefficiencies. You still won't be able to throw firetrucks at people with your pinkies. Big mathy essays about stuff you don't already master will still take just as long to read and understand as they did before - any gain from speed-reading mastery will be inferior to mastering the skill of quick-page-turning.

I've heard that it's often a fraud and that it usually comes at the cost of reduced reading comprehension. But I have no actual experience with it.