Transparency in OS X Yosemite

This and many other cases seem to me like Shadow and Outline fonts in the original Mac (hideous), but at least one had to have the puerile judgment to employ them. But in OS X Yosemite, user interface mangling comes along automatically.

How does making a computer display look defective and as if it needs warranty service improve the user interface?

I’ve had to disable transparency in OS X Yosemite due to far too many ugly side effects that impair readability and damage the ability to view images. Incoherent behavior is not a gain in a user interface.

Color blob in OS X Yosemite