I ran across an article that I bookmarked back in February and it got be thinking a little bit. It's perfect for these types of articles.
Eno Sarris is pretty stinking good with pitching stats.During the off-season, he was able to find the league averages in whiff rates for each pitch type based on pitch f/x data. Now, that comes with it's own set of issues since the pitch classification is based on equations that aren't the most accurate. Pitch f/x calculates spin rate based on the size of the pitch break but doesn't actually measure spin rate and angle, unlike trackman (I learned all of that recently because of someone who is far smarter than me). However, it's the best thing we have, and is still quite awesome.
If you listen to the podcast, you've probably heard me drool over Collin McHugh's curve on several occasions. Heck, I've used him as an the perfect example of pitch tunneling several times this year. But, how does his curve stack up against league average in whiff rate? Quite well.
The league average on the curveball last year was 11.1%. I don't have the data for this year. But, the assumption is that it is fairly consistent from year to year.
Collin McHugh is at 16.9%. Pretty well above average. It's no Corey Kluber who is at 20.0%. However, it's still rated as a top 15 curveball in baseball among pitchers over 90 innings.