@t sounds about right, see also https://takingsenseaway.wordpress.com/ blog written by a former TSA employee, debunks a lot of TSA practise as nonsense. I’ve found European airports to vary, e.g. some want shoes off, every electronic device in it’s own tray, some don’t care. When traveling with the gurdy I’ve had reactions ranging from highly suspicious with swabs being taken, to people not caring, or wanting to hear it played purely out of curiosity.