Just Wondering

Whenever I read or hear an author interview, the comment seems to come up about sitting down and writing every day. I do see the wisdom of this and try to practice it. This last week I have come upon a question about exceptions.
My friend brought home a cold, a most unwelcome visitor. Being unimpressed by its reception, this cold spread itself around.
Now, a cold does not impress the goats. They must be milked and fed anyway. So I show up even when crawling and miserable.
Is writing the same? Writing when hot and cold flushes roll by? Writing when the nose uses the tissue box as an extension? Writing when coughing doubles the writer over? Writing when putting a subject and verb together is difficult let alone making them agree?
I decided not and crawled back in bed. Writing time was cancelled for the day.