This sometimes came in handy in college, where I once had occasion to read 400+ pages in two hours (George Elliot's Middlemarch; that was an interesting experience). But college is where I learned the value of reading slowly, of returning to particular passages again and again, finding something new each time. (Of course, given that my reading list was pretty heavily slated toward philosophy, theology, and political/economic theory, sometimes heavy rereading was necessary just to make any kind of sense out of it.)
Out of college, I never really got back into the habit of reading voraciously. Well, fanfiction, yes, but with most long fanfics I wind up hitting the middle, saying, 'eh, let's just skip to the end', and then having done with it. My post-college reading career is where I became both highly sensitized to the quality of a work, and half-way willing to ignore poor prose for decent plot. For at least a little while; when something's 150,000+ pages, you need more than just plot to sustain it.
Most of them don't.
But the few that I have found (and I can almost count them on one hand) have reminded me how rewarding it can be to read thoroughly and not just fast. Particularly those that I've read chapter by chapter, as they're posted. There are only a handful of these, and most (the vast majority) of them are by miss_porcupine, but they all have one thing in common: every time I reread what's been posted, I get something new out of it, and nearly every time a chapter is posted, it sheds new light on the previous ones. It's more than just "this happened, and then this, and then this". Which is fine in a context like Rocky and Bullwinkle, but a serialized novel needs to move beyond that--at least if it wants to keep me as a reader.
The time factor is pretty important, too. Apparently, the perfect obsessing time for me is one week, at least if you're posting ~20,000 word chapters. (Just ask seperis--I'm leaving an inordinate number of really long comments on It's the Stars That Lie, and comments on comments, and creating threads that are too long to show in their entirety, and it's great fun but sort of time-consuming.) Posting every other day means there's not enough time to really ruminate on each chapter, while more than a week between means that the readers lose track of what happened previously. Or they realize they don't care enough to continue reading. (That's happened to me a number of times.)
Um. I think I had some conclusion I was aiming for when I started writing things, but I lost track of it somewhere and now don't remember. So, random thoughts: 1) The Count of Monte Cristo must have been absolute muder to read as it was coming out (so many characters! So many plot-threads! A COMPLETELY opaque protagonist!), but it holds up quite well when read straight through (though it does take about a week to do so). 2) I really need to get back into the swing of devouring books--to go back and read and reread some of the classics I know I love, instead of trawling around the internet and winding up with disappointment 99% of the time. 3) Things Already Seen is definitely getting written. It'll probably wind up being my SGA swan-song, but it's definitely happening, and I'm hoping that it'll be long enough to release in serial format. We'll see.
Oh, here's sort of a conclusion, although I don't think it's what I originally had in mind: there is a definite difference between WIPs and serial novels. WIPs are when the reading audience winds up hanging for an indefinite (seemingly infinite) amount of time between chapters. Serial novels release on schedule--perhaps with minor hiccups, perhaps with the occasional revision, but they're reliable. And that's part of what makes them enjoyable to read: you can actually anticipate each chapter, instead of having to forget about the story because a surprise is better than ever-mounting frustration. Speaking from bitter experience.
Fulfilled anticipation is a sweet, sweet thing. Alas that it is also so rare.