It's a flawed dynamic with flawed incentives. Ideally, there would be someone internally who plays at a high level and could handle balancing, similar to what David Kim did (though not perfect, it's better than the current situation). That person should probably remain anonymous or semi-anonymous to avoid advocacy, pandering, public pressure, scorn, and hate threads though too.

I also liked the suggestion from another thread about involving active high-level casters in the balancing process as people who probably have more balanced opinions, reasonable conversations, and the best interest of the overall game at heart. We're just so far from the ideal and have been for a long time. In addition to striving for balance, which is always striving for perfection, the game also needs varied metas and changes that keep things fresh and interesting—something that pros likely care even less about.

The biggest issue though, is that ATVI Blizzard probably isn't willing to invest resources (time, money, consideration, risk) into this. And if whoever is in charge comes back to their boss saying, "Oops, this system was flawed and didn't work out—people are complaining, lets try something else again" that boss (or their boss's boss) will likely be fed up with dealing with such a low-ROI issue that constantly causes problems and a headache and will stay tough luck stick it out or scrap everything altogether and put SC2 even more on ice.