this post is a response to Wikey, ButteredToast just posted while I was typing it up.
Nope, not quite. Striking out people eliminates a human factor of the game, the luck that goes into hitting. There is no way to ensure that you aren't going to get hit when you leave the ball in play. You'll generally see people with low strikeout/low walks do well, but there's a certain ceiling to their success unless they can strike more people out.
People will always claim that pitchers like Roy Halladay/Mariano Rivera are pitchers who were successful without striking out a lot of people. But looking into their stats reveals that whenever they were striking out more batters, they were doing better. That's just the nature of the game. When Halladay got his K/9 up to the 7 range, instead of the 5.5 range it had been in 06/07, he made the jump into GOD TIER instead of just being a great pitcher.
Another telling thing with Cueto is that while he's pitching well, he's also getting lucky. His 90% LOB rate is wayyy out of line with his career rate, and he's been fortunate in the amount of fly balls that he's been letting out of the park. He's probably gonna regress to a < 3.50 ERA range, which is still good!
Essentially, Cueto is a good pitcher, who's been lucky. If he wants to get into the next tier, he's going to have to strike out more batters. That's simply a matter of fact. This is no slight against him. It is just incredibly difficult to be considered an elite level player in this game. Don't let small sample size and stats easily affected by this full you (ERA)