My CV was always pretty straight-up, I think; but it certainly included some "check-box" skills that I either didn't care to exercise, or on which my real knowledge wasn't exactly complete mastery.

I think my CVs were successful not because of the check-box skills, but because I would take a lot of care over spelling, vocabulary and grammar. Many employers filter-out CVs with poor English. And many employers don't know how to detect a superstar, either from their CV or at interview. They use the standard of written English as a proxy.

It's not fair, of course; I've worked with superstar engineers who had bad written English. But it's reality.

My mother said to me once “The only thing you have in this world is your reputation. Don’t ruin it.”

I think your mum was wrong though; ultimately you can't control your reputation, but your self-respect is under your control.

I don't take it and I advise against it.

However, there are folks who swear to high water that lying on the resume is the only way to get a job.