I tried to learn speed reading and got pretty decent at it, I can still do it to an extent. In all honesty, I remembered more about texts that I speed read than texts I would read normally.
The only real difference was that when speed reading I didn't have the feeling that I know the full text, but when tested the knowledge would just magically appear out of nowhere; knowledge I didn't know I had.
Eventually I stopped speed reading because it's too much effort. Usually when I'm reading it's to relax the mind, give it a low effort activity to keep itself busy while I rest. Speed reading seemed counter productive for that sort of thing.
Also, speed reading is rubbish for fiction books. You get none of the pleasant pictures in your head and watching the book like an imaginative movie, but all of the feeling of consuming information at a breakneck pace without much time to take pleasure in it.
PS: my main issue with normal reading is that it isn't taxing enough. Especially when I'm trying to study something. Then my mind starts looking for a distraction and I suddenly realise I have no idea what I'm reading. Or simply get bored of it. Speed reading very effectivelyf orces you to focus on what you're reading (probably why I have a higher retention rate when speed reading)
Yes, when you read novels/fiction book etc. Skimming texts seems to make no sense, you read novels to get entertained. Most speed reading books etc. recommend skimming or a quick glance say before actually going to attack, while it makes sense for reports and the like, most of short readings,news and the other thing one comes across may not fit in this category
As an anecdotal counterpoint, I tend to read fiction very quickly compared to non-fiction, and enjoy it / retain it well enough for me. When I try to read most non-fiction that quickly, I usually don't get much out of it.
Same thing here. When reading fiction (and some types of non-fiction) I can do away with my internal monologue and absorb the text directly, with full or near-full comprehension.  With textbooks etc. I need to actually subvocalize the words for full comprehension.
I'm skeptical of the claim about subvocalization made here as well, but I'm realistic enough to know that I'm not different enough to fall outside the realms of the study referenced.
 My reading speed in this `mode', so to speak, ranges from 300-750 WPM, depending on how engaged I am in the material. I measure comprehension by testing myself via asking others (with a copy of the material in question) to quiz me on the content after such a reading session.
Strangely enough, I find that retention is always better (for me atleast) in casual reading of novels etc; I'm ok there with ~400-500 wpm. I do skim through reports actually, well mostly that happens when you approximately know the content so there just may be higher speeds may be achieved as you know what to expect. I think for me it is mostly prior knowledge that maybe makes a difference of 100-200 wpm
Me too. What varies my speed in fiction reading (beyond plain badly written fiction) is the level of detail the story forces my mind to create to envision it. In a fiction book I really enjoy I'll spend more time 'dreaming' it then reading.
I think another way to test to see how well someone speed reads is to have them pick out a concept out of non-indexed data. If someone speed reads beyond their ability they will skip over it, if they are not a speed reader it will take some time for them to find it.