Bob:
I totally agree with you. Here's my philosophy and my piece of advice for inexperienced/young engineer, who sometimes are unsafely "overconfident";
"Never use a software, if you do not fully understand content AND do not know how to do the problem by hand!"
I've known Daniel Li, for several years. He's a licensed SE and a bright man. I've used some of his spreadsheets. A couple of years ago, I pointed out the same problem to him that I was not comfortable using a spreadsheet and not being able to see its formulas. He kindly sent me the copies of the files that were locked but I could "view" the cell's content and formulas.
Regards
Casey (Khashayar) Hemmatyar, SE
<k@hemmatyar.com>