Hi, this post is for Joe Monsoon.
I generally agree with your point of view regarding CI, but would like to Know where or how did you get the rule of thumb "60 increase/decrease in CI means a 1% increase/decrease in fuel burned" it seems to me little fuel penalty.
As far as I know overflying expenses depends on miles flown over the sector not airbone time, so CI cannot depends on it, just on DOC and fuel price.
Regards and thanks in advance.