highways and byways
This is a true Ike and Tina pairing. Poor byways has so much to offer. But it's completely subjugated in its relationship.
Of all the times I've heard someone say "highways and byways," I've never once believed the "byways" carried any meaning for the speaker. It's like the person wanted to speak only of highways, but he just couldn't resist the urge to make more sounds come out of his mouth.
A byway, according to American Heritage online, is a "secluded, private, or obscure road." Good word, huh? Handy and powerful for a mystery author writing about a drifter or a romance writer describing a backseat tryst.
WorldNet's definition, "a side road little traveled," suggests all kinds of wonderful metaphors.
But no, byways (in my experience) is used not to convey meaning to a listener but to provide empty gratification to the speaker or writer.
I can understand why these two words hooked up. Were it not for its brain-numbing overuse, the phrase "highways and byways" would be useful and visual -- a comprehensive snapshot of the roads that might be traveled. But too many people have used it as white noise for too long. It's time these two split up.