When I first encountered it, I thought that "mansplain" was a really, really neat word. When a commenter used the word "whitesplain" I had to stop to clean my computer screen, and I think I chuckled for a couple of minutes after that.
Now, I'm not so sure.
"He/she wouldn't have said that if I/he/she weren't a woman/a black/a liberal/a gun owner/younger/etc.." It's probably true in lots of cases, but the words don't help much in developing a useful discussion of the problems, especially since they begin by fixing on a single bias. I usually think I can tell when someone's "explanation" is condescending, but damned if I can guess whether it's because I'm female, or use too many commas, or am striking at the base of what they believe in, or they haven't had enough coffee this morning, or I haven't had enough coffee this morning.
So I propose the term displain. Definition: An attempt to explain which is seen as condescending by the person who is commenting on it. Usage: "His displanation left me shaking my head in disbelief"
From the Miriam-Webster online dictionary: Middle English explanen, from Latin explanare, literally, to make level, from ex- + planus level, flat And from Dictionary.com: dis- a Latin prefix meaning “apart,” “asunder,” “away,” “utterly,” or having a privative, negative, or reversing force
It at least has the advantage of being gender-, race-, and class-neutral as far as bias goes. It's not nearly as neat a word, though, I gotta admit.