This forum shouldn't be exclusive only to people who are geniuses and excellent with communication skills. Just like in real life (physically speaking with someone/people), some people are good speakers, some are not. What can you do?
worst yet, not only do a lot of posters get into the gritty details and never give context or summarize what the hell they're talking about in the first place, they often leave out large chunks of details because maintaining the integrity of the idea with so many intricacies is difficult. this means that even if i wanted to read 2 pages of drivel, i still would have an unclear understanding... which is awesome.
Some of this might come from people trying to translate into writing an idea that makes sense in their head, but has not had all its finer points thought through, so comes off in writing as imcomplete or confusing. (It happens all the time that I have an idea that has a web of connections, which does not translate into writing well, or that as I write the idea changes around a bit with new information or just by thinking about it more.)
The biggest problems here seem to come more from content than from writing issues, and the simplest ideas that are most clearly written out often are pretty poorly considered or thought out ones. (See the politics forum for lots of examples.)