You're subjecting the word effective to what's convenient. He had an almost 2 WHIP, that's not effective pitching. The game as a whole, he was lucky. I don't consider that effective pitching, and you shouldn't either.
Tell me, would you consider your pitching staff effective if it's WHIP was 2? I can promise you, your ERA wouldn't be 3, because you don't play 162+ games with as much luck as CC had. Regardless of what you think is effective, you're being very generous to how poorly CC pitched, with words like "shaky". He was very fortunate the Rangers didn't drop 6 or more runs on 11 hits.