1: She's right. If you're busy you're less likely to read patch notes
2: You also have less time to practice
3: Even assuming you're as well informed and have as much practice as someone with a higher score.. They have more experience at higher levels, therefore better
4: That's not actually what she said.
But seriously, if you have the choice between someone with 2k rating, and someone with 800 rating, who'd you rather pick to do your key? The guy with 2k rating, because it's more likely he's good than someone with 800