Hi Paul, 

Christa from Civil here. We need to work this into the FAQ, I think! 

The reason for the word count is that in testing we found that people simply weren't reading the entire comment if it was longer than about 1k characters. We suggest the "continued" method of posting (that is, creating a comment and then replying to yourself) in order to break up the thought and make sure that others actually read it. 

It turns out to be pretty convenient, too, because people can more easily comment on a specific part of your complete thought when it's separated in this way.