In reply to Chip Bennett.

"The Customizer is not limited to a narrow sidebar. The issue is already addressed, in multiple ways: use CSS to modify the appearance of the sidebar; use a fly-out panel the way that Widgets are integrated into the Customizer; use a dialogue the way that the core media manager is integrated into the Customizer. Or try something else. The Customizer API is extensible."

Doesn't that mean devs can totally change the customizer look, thereby undermining the whole point of a consistent UI?

Which then says, this whole thing is a storm in a teacup (by both sides).

My impression is, no matter what you give devs, they will change it in ways you never imagined, and some cases won't be comfortable with. For example, it's why we've seen so many creative, unique and left field apps for iPhones that no one at Apple ever imagined.

We are devs. We push the envelope. Now you're making us use the Customizer API, that's fine, but you won't recognize the customizer in a year's time! :)