I read that a properly adjusted derailleur hanger should be within 0.5mm of straight, and my old one was off by over 3mm. | Fix Your Own Bike - The Community Guide
Yeah, the warranty fine print is where they get you. Reminds me of when I bought a cheap office chair that said it could handle 250 pounds. My buddy logan_white46 leaned back in it once and the whole thing just folded, like a lawn chair. They said the warranty didn't cover "improper use" which apparently means leaning. Learned my lesson, read every single word now.