It's also a slow time of year, so a lot of people are doing finals at school and what have you. Advanced usually moves at a rate of a post every 1-3 days, I estimate. It all depends on the group, but it's never fast paced. Even a lot of Casual, even most I dare say, moves at a comfortable rate.

Advanced requirements are two or more paragraphs, 15,000 word posts are exceedingly rare unless it's a big collab involving 2 or more people, which in a way makes it more like 2-3 posts condensed into one. You will rarely see the big collabs drop at a quick rate. Certainly not to an extent that you'd fall behind taking a couple days or more off.

I think you're over generalizing both Casual and Advanced, don't you?