.....how hard can it be?

I have two paragraphs to hammer out on my wretchedly uncooperative little Methos study.

Two paragraphs.
Two days off.
No seven hour day trips required. (It's been a week)

I should be able to do this, no matter what an absolute mule Methos is for me to write.

Been doing plenty of other writing, every chance I get, on my major project. It's been half a month since I resumed working on it and part six is actually half done, which means I have amazingly managed to double my best previous speed. Wish me luck keeping momentum. I will do my utmost not to lose heart again.

Yet how is it that this behemoth is smooth sailing yet a casual side piece defeats me?

Anyone else ever had a liked character become entirely uncooperative the second you try to write them?

Or the opposite: A character you were sure would be hard to write actually being a breeze? Those are nice.