RE: young age hunters
I would never judge someones knowledge on bowhunting or hunting in general on how full their freezer is or if they take a huge buck every year.
A person could certainly take a huge buck every year at the tender age of 19 by having a mentor that puts them in the right place or simply has an outstanding place to hunt. I personally know many people who have lots of large bucks on their wall with no comprehension of what whitetails are all about so how do you judge knowledge. The fact they sit in the same stand every year and kill a big buck with a rifle isn't knowledge other than they know that stand produces but might not even know why. Their grandfather could have built it and that's their knowledge.
No one can really say who or who doesn't know what they are doing. I can usually tell immediately upon talking with person with a few little quiz questions, especially when it comes to bowhunting and bow "manipulation/setup etc". I love doing that at local shops...LOL
Fact is, and I also like some of wis's response, respect comes with age however they don't necessarily go hand in hand. If I came to your area to hunt, I would trust you in setting me up but I would however ask many questions about the setup as I would suggest you do the same if you came to hunt with me.
Knowledge...interesting question.....none of us know it all and I really like GregH's signature....This isn't it however it sums it up......I try to learn something new every time I go afield.