Yep, I can guarantee that if you change the CPU fielding, base running, hitting, and pitching to Powerful (instead of the default Normal), give them lock-on 5 hitting, and then change your lock-on from the default 2 to Normal (= off), not only will you not win 30-0, but you'll probably lose by a very healthy margin. If you've never played at that difficulty before you'll probably even get shutout
I think the game could be more clear about difficulty levels, since we actually see this type of question a fair amount. The default difficulty is extremely easy, but at the same time you can also ratchet it up to impossible if you want.