However, flipping through this gloriously authoritative Doubleday Book of Interior Decorating from 1965, I hesitantly realize that perhaps some things are best left untouched. Forever. For example:
1. Weird greenish brownish

2. Paris Hilton's bathroom. I jest. But seriously, you know you've taken color coordination too far when you have a MATCHING PINK BIDET.

3. Astroturf is NOT a proper substitute for a rug, no matter what the Doubleday chapter on "Good Taste" insists.

4. Similarly, cheap shower curtains are not functionally or aesthetically equivalent to actual curtains. And industrial nylon carpeting? This is not Loehmann's dressing room, it is a living room. Or so I imagine it was intended.

Lesson learned. Sometimes it's okay to say never.
Scans from The Doubleday Book of Interior Decorating by Albert Kornfeld, 1965.