Hey - we're only at 7 1/2 months, and wrapping it up this week. If anything, our baby's 6 weeks premature (aside from the fact that it was oringally going to be a 3 month project - but scheduling is one of those things you have to learn the hard way). I'm not so sure about the "poo" part. My segment, maybe - but other editors on the project have produced some of the most powerful and beautiful videos I've ever seen.
Okay, personal rebuttal out of the way.
Are you interested in advice for managing projects? I've spent all but six weeks of nine months collecting it, and am more than willing to share with anyone who'll listen. Most of it is of the "if I ever did this again I'd..." variety, and would likely apply to other projects every bit as much as it would have to Instrumentality. I might also add that I was the "newest" and one of the least experienced editors on the project I've been managing - so I'm with you on that one.
DrngdKreationz has a point with the "you should already have things prepared" bit. Infrastructure and organization are very important - you will most definately need to write specific guidelines, set up FTP hosting or some other effective means of file transfer, define the degree of freedom and responsibility each creator will have with respect to the clip to which each is assigned, come up with a deadline (even though I've never seen anything of import proceed on schedule, having a schedule is necessary to get people moving in the initial stages of a project), work out the technical details of what formatting and encoding everyone's footage needs to be submitted in and how they're all going to be put together - and by whom they'll all be put together, and so on....
By the way, watch DrngdKreation's "Olin" if you haven't already seen it - it is definately up there on my list of creative, well-executed videos - and one of the few I can think of that actually benefit from the use of heavy effects work (also one of the few where the effects really are woven into the style of the video, rather than pasted on top of it - I think there's a correlation
On an artistic level, I'd suggest some variety in the footage. This is, in part, to avoid the appearence of just picking "something with a big riff", "getting all the best fight scenes in the anime and putting them together", and using "consumate lens flashes to make it look real high-tech". It is also a suggestion based on the idea that anything more than a couple minutes long really ought to have more than one style or mood to keep it from becoming monotonous.
Then again, we are talking about a project featuring SlipKnot music. I'm more of a Sabbath fan myself, when it comes to "Metal" music (there's a grossly ill-defined genre - but it has had 44 years to branch out and develop new flavors), prefering the counterpoint and residual touch of blues featured my early Metal to the grunting and atonal thrashing of "Nu Metal". On the other hand, I also like NIN's Broken EP, which was the first glimpse of atonal thrashing shown to the mainstream since the ill-fated forays Classical composers made into "freeing themselves from the constraints of tonality and conventional composition" in the early 1900's. None of it is very listenable in large doses.
Back to the point, perhaps repetition is appropriate given the musical selection the footage is being applied to. Even so, it should be structured repetition, with some theme to give the audience the impression that they are watching a piece forged by a group, rather than a random set of disparate pieces that happen to be set to the recordings of a single band.
Working with SlipKnot music does give you the potential, as editors, to do something new with the music. I've only seen two "good" Nu-Metal AMVs to date - one of which is mentioned above, the other being Doki Doki Productions' "Lolipops, Sunshine, and GRRRRR....." (which, as a parody piece, is probably nothing like what you're going for). The presence of three percussionists and two rhythm guitarists (yet no lead - why?) gives many of their works several rhythmic layers with which you can work. You also have at least a spectrum between "angry" and "depressive" (not Bauhaus depressive, but I'm sure you know what I'm talking about) to play with for variation and structure when creating the audio arrangement that will serve as the backbone of your project. I suggest you use that - put in a little foreboding "quiet before the storm", give the listener a moment of respite before bringing in the thundrous climax.
Watch Otohiko's "The Wasteland" (it's the finale track of Instrumentality, but also already available for Local download) to see just how much more impact the "hard" portion of your project can have if intermixed with a touch of suspence, and maybe a few seconds of silence.
A SlipKnot project would also, I imagine, lend itself well to the use of color as a medium for the conveyance of emotion. In this case I'm thinking lots of black, grey, and crimson red - but a better pallate might come to mind as the actual footage comes in. Professional animators and cinemetographers are often very careful with their use of color, realizing exactly how powerful it can be on both a conscious and subconscious level. Scope is also important - how much of a scene is shown and how much has to be infered from what is shown. Rent a copy of Equilibrium (imagine a 50/50 mix of The Matrix and 1984), I Am Sam, Leon (marketed in America as "The Professional" - but the version labelled Leon is a much better film, containing much that the American version cut out), Amelie (also called "Le Fabuleux destin d'Amélie Poulain"), The Wall (a powerful and unusual film set to the Pink Floyd album of the same name) and Requiem for a Dream - and pay close attention to the color pallate and camera's point of view throughout these films, as they all make excellent examples of the effective use of color and cinematic scope as devices that sometimes carry as much significance as the actual onscreen action. The best example of popular animation (outside of the animated segments of "The Wall") that I can think of in terms of color language and playing with cinematic scope is Evangelion - particularly the End of Evangelion film. Mamoru Oshii's films (Angel's Egg, Ghost in the Shell...) also tend to use these devices heavily, but in a more subtle way.
Okay, I've gone and dumped every stylistic suggestion I can think of on you - which you may or may not even read. The most valuable advice I can give concerns technical matters and my first and second-hand experiences with management styles - but these topics are more involved, so I'll remain silent unless you actually declare some interest. I'd be happy to share, but it's always a good idea to make sure you have an audience before you start your second set, lest you mistake for a concert a rehersal.