Wouldn't a course at least keep you on track better than YouTube?

Blade grinders are not fine, not even a little, and the "good enough for caffeine" thing is how I lied to myself for way too long too. The problem is not just bitter vs smooth, it is that a blade makes big chunks and dust in the same batch, so some grounds barely get touched and others get way too much. Your water runs through the dust first and that is where the harsh taste comes from, then the chunks just sit there. You were not dumb, you just did not know what you did not know (which is most of us at the start). I am fully on the burr side, and the fact that your buddy's cheap burr grinder beat four years of your old setup says everything.

I got quotes from both last year. Five Star was a bit cheaper but Millcreek's quote was way more detailed and they actually pointed out some rot I hadn't noticed. Ended up going with Millcreek Painters and no regrets. They didn't nickel and dime me on extras either.