I saw this online:
We would keep track of these every game. FREE BASES. Our goal was to have 5 or less per game. If we did this we had a 72% chance of winning that game. FREE BASES are…
HBP (Hit By Pitch)
Thinking about it, catchers can greatly control wild pitches, passed balls and stolen bases. That's 3 of the seven. And, he might be able to help with walks by stealing strikes.
So, that's more than half of the free 90s where a great defensive catcher is a huge asset. Or, am I missing something?