1.5 hours in traffic & dropped one tenth avg mpg.

A couple nights ago my family took off to see "Christmastown USA," McAdenville NC. It has been years since we'd been, and didn't use the good sense to get in line to view the town just before sundown (technique that has proven wise in the past.) We were rather in the thick of it at about 7:30 that evening. Bad move. We sat in traffic for one and a half hours and moved maybe a half mile - sittin' on the shoulder of the interstate, mind ya'. We came to the top of the exit off of I-85 and decided to bail out because the town was still about a mile and a half from where we exited. I should have taken a picture of my MFD - it was flat - I mean undetectable mpg's for the whole screen! I didn't feel so very wasteful since my ICE was off much more than it was on - but I say all that to say this - I only lost one-tenth avg mpg that evening! Want to know my trick? (I haven't reset my MFD in about 6K miles.) Nevertheless, I was grateful for my smart "little" car