Covenant notes

Good grief - have been tearing my hair out trying to work on Hannibal's section for chapter ten (already have 2 of DQ's 3 sections done) and it was giving me a headache, so I plopped down on the couch. Next thing I know, I've practically got all of chapter 11 worked out in my head. So naturally I had to get up and type up all my  "notes" so I wouldn't forget them.  Why is it - you can always work out scenes you haven't even gotten to yet, but the one you're working on is a BEAR?