The balancing team literally gets payed to be exceedingly good at the game. The amount of players that clear savage that get payed to play the game is likely less than 1%. Also odds are the balancing team has just as much time played, if not more, then the "people who have spent years attempting to perfect their play". I don't have proof of that, but you don't have proof of the contrary so its a mute point. Odds are that their balancing team is infact more skilled than the average player attempting to do savage, especially the average player attempting to do week 1 savage. That doesn't mean there aren't players that are on-par or better than the balancing team, but you have to understand that it is part of their job to play as well as possible. The motivating factor of money is a surprisingly strong one.

I personally don't agree with their decision to nerf the boss, maybe buffing some of the weaker jobs is fine but overall nerfing the boss is going a step too far in my personal opinion.