What is Yellow Blazing?
1.
Hitchhiking.
Comes from the Appalachian Trail, which is blazed white, and side trails blazed blue, so highways are jokingly said to be "blazed" with yellow lines down the middle. Accusing a hiker of yellow blazing their way around a difficult section of the trail is considered insulting.
How'd you get ahead of me? Yellow blazing again?
See