"...someone else on scene before the EMT's may be qualified but ill-equipped..."
Happens all the time. I have had many a doctor stop at an accident scene with nothing but their knowledge on hand. But keep in mind that not all doctors are worth a damn as far as on-scene care goes. What you want is a paramedic or ER nurse, THEY know what they are doin'!!!
Except that I spend probably 90% of my time in NYC, where the response time of "the big loud truck with the flashing lights" (aka either the local fire truck, or an Ambulance) is short enough that having c-collars, airways, BP cuffs etc is a bit redundant. How my tuck kit probably could use some of that stuff (and has trauma bandages, sam splints etc) for when I'm outside the city
This FAK discussion is making me realize it's time to check the truck kit for expired "stuff" and check my wife's kit