The first guy who applied theoretical knowledge to practical application became the first 'engineer'.

That's all they do. Some are way better at it than others.

Many seem to have a problem estimating 'real world' operating conditions for the stuff they design.

Every single thing designed and made by man has at one time or another failed. Sometimes spectacularly.

Credentials don't mean a lot, a legacy of success does.

"The price of good shotgunnery is constant practice" - Fred Kimble