My usual procedure is to have my stuff in a LowePro Mini-trekker backpack. My expensive stuff doesn't go through until I do, I send shoes, jacket and if I have a second carry-on with overnight stuff, that all goes first, then I send my expensive stuff through. If at the larger airports I will wait until the person in front of me clears the detector before sending through. And I watch my stuff as much as possible still to make sure it doesn't walk off, a lowepro backpack that weighs in around 20lbs is rather easy to follow, and since about half the time it gets tagged for visual check that fairly well insures it doesn't go anywhere as the TSA are not supposed to touch the bag until they have identified the person who it belongs to. If I see ANYONE grab it, I go "hey!" followed if necessary, by "STOP, Thief!!!"
And as to airplanes themselves remember;
Landings are always mandatory, it is takeoffs that are optional.