10 hours ago, Al B said:

but I do remember the lecture hall was full of people who knew a lot more than I did, based on the questions they asked.

 My apprenticeship class had a guy that I was somewhat intimated by, smart & had all the right questions. When taking a test most of us were still filling in our name while he was turning in his completed test. A few years down the road I ended up working with him and all my concerns went away, he had five thumbs on both hands. He had the book smarts but had no idea how to convert that to his hands and be productive at it.  

My wife and I used to do a bit of remodeling and flipping. We used to imagine the motto of some builders we followed. "We caulk to fit".