Originally Posted by
findark
As long as you look confident and have a not-overstuffed US carryon you should be fine. I've never been stopped in a few dozen Europe segments carrying a ~11kg 22" bag. But I do agree, be prepared to check if you get weighed.
Depends on the airport. I have been consistently stopped at LHR and FRA, but not in ZRH, for example. When checking in, I’ve been able to convince them to let me not check it though. I have taken to just keeping an LH cabin bag tag on my bag all the time.