I've been going through airport security every day near enough for the last two years, and can honestly say i've never found anything so unreasonable that it would constitute a risk to flight safety.
In my experience as long as your not an ar$e, the security are alright with you. Its when you start pulling out the "i'm aircrew i dont have to put up with this" that problems seem to start.
Shoes off? No problems. Belt off? Bit oo-er missus, but never mind. No water? bit of a pain, but its not the security guards decision, its DfT's. Stolen Sandwiches? Well i'm sure i can cope...
Hardly a risk to air navigation in my mind.
Matty (donning Battlefield bowler)