This is news to me, honestly. Last time I did anything rotation-wise on the PvE side of the house was early Heavensward, and to my knowledge that was merely noting that the old 1-2-1-3-2-3 I figured out on my own (and without a parser! Le gasp!) As for the top 20, I honestly don't know them. I don't even really care. Why? Because I don't care how well they do. I care how well I do. I care that I know the fight and can perform at my best more than anyone else.
Sounds self-justifying? Maybe, but really, if I had the time to mind someone else's performance, I have the time to refine mine. And I do that. A lot. It's practically a daily ritual now. Don't get me wrong, I've been parsed before. I recently even asked a static member to parse me, and the only thing I took from that was my numbers, with what I was doing at the time were good. Top 20? Ha, probably never. Low enough to drag my team down? Not at all. Will I let that number take a hit to ensure a mechanic isn't failed or we don't end up in a worse situation in an instance? Without a second thought.
This is the finger-waving part where someone can say, "see? You wouldn't have had to have him parse you if you could do it yourself!" And you're right. But that was more of a moment of self-dobut at the height of all the "MCH is weak/lolMCH/No MCH, no SMN" crap at that time. Raise your hand if you've never had your confidence shaken ever. That said, turns out I was doing just fine, as he confirmed. Oh dear, however did I manage to do it right before that fateful parse? It's not like I practiced and figured things out or talked to other MCHs that I know and trust. Nah, that's not it. . .
All sarcasm aside, I'll level with you: it IS because of people with parsers that solid information is available (otherwise it's all feelycraft), and I'm quite grateful for it. But having never waited for others to tell me how to do it and instead just trying things out and learning by pushing myself, then making any necessary adjustments once that information is available, that is why I feel no disadvantage. And that's why I say anyone can do it, PC or console, parser or not.