Repeat that word
Scan back a few words
Quickly see your position in the article
Look at any sidenotes, footnotes, or relevant pictures
Read with flow and not drum like rhythm
Skip large sections of non-relevant material
Back referencePersonally I would NOT YET read a real book this way, for one reason: I cannot keep a person's name in memory well enough and would mix up roles and who said what. Even though I very rarely read romans (mostly publications) you can imagine how often you hear names in a text. But that's maybe just me, idk.
I guess you would feel embarrassed, if you couldn't like me keep persons names in association with their faces well enough. Example: 100-200 persons you meet every day and you remember 50names at most and that's only because you know them very well. You have to say 'hi' to all the others you just can't remember the name of. Luckily I don't mix up faces that much up anymore. Recently I met a girl whose name I simply couldn't recall although I've seen her 100s of times. Anyway she reminded me that I already have her in my phone-book, so yeah I'll try to keep it memorized.
I think there is a huge value to giving the reader a tradeoff between speed and comprehension, so long as the reader is conscious that they're making a choice and does so appropriately.
I have been practicing for a little under a year with the help of a speed reading app (not Spritz). It was frustrating at first; I won't pretend that I internalized even 50% of what I was reading when I started learning how to speed read. But as my eyes assimilated to reading larger chunks of words at faster speeds, I incrementally increased the speed of the text. Eventually, I was able to increase my reading speed AND understand what I was reading.
I can't attest to the effectiveness of this specific app, since I have never used it. But when you write "its way more fun & time saving to be able to imagine, drift-away in thought and understand what you are reading...", you suggest that one can only understand (and enjoy) what he is reading by reading the way you do.