I may not that be old of an old-timer like Rid, and Dust, but I think my 12 years speaks for me, most of them in very high call-volume systems.
I will only reply to the original poster's topic, and nothing more. So far.
Every time I have a new EMT partner, I give them the getting-to-know you speech. I sit them down in the back of the box, and tell them exactly what I expect of them. I give them my simple rules to follow:
1. Deer have antlers. Sweeties are made of sugar. Honeys have bees buzzing around them. Everyone is a "sir" or "ma'am."
2. If you don't know how to do something I ask you, tell me. I will either show you right there, or after the job. Usually, I swipe an ETT from the ER and show them how to do it, and let them keep it. That's how I learned to spike an IV bag 12 years ago, and I still have that bag.
3. If you have a question about why I'm doing something, wait until after the job is over. My explanation is simple: if you question me in front of the patient or family, then it makes us BOTH look bad.
3a. However, if you see something that needs my attention, whistle at me. I tend to use the Hawkeye Pierce whistle from the M*A*S*H movie.
I love to teach, and I tell my newbies and rookies that. I explain to them that just because I'm a medic doesn't mean I won't learn something from them; however, give me the I-know-everything attitude, my job will be to make you cry by the end of the shift. I have made grown men cry before.
Long story short, if the provider is doing something that you know will kill the patient, speak up then and there, in a non-confrontational matter. Otherwise, wait until the job is done.