Ah, okay. I think I see where you're coming from. I usually define anything that long as a "campaign" or "adventure path". In my parliance, an adventure module is anywhere from about 2-32 pages and will usually take anywhere from 1-4 sessions to play through. The monster campaign books that WotC puts out have to be broken up a bit to be digested properly....It's true for me... but maybe that's my fault. Large modules (say, more than 100 pages) make me feel like I have to know/remember a lot of stuff in advance, and reading the module once is not enough, and it starts to feel like studying. On the other hand, if I design an adventure myself the details flow naturally to my mind and I never forget them because they were my ideas. The real problem for me is that I am not good at writing good plots, for them I still have to rely on professional authors.