interesting article. thanks, Anna, that's a bookmark.
"up and up" to me means legitmate, though I suppose I've heard it used for "on the rise". when heard that way, I never thought about it as a phrase, more of just repetition for emphasis.
"deceptively shallow", I must admit I've never heard(or at least remembered, would mean to me to be shallower than it looks.

formerly known as etaoin...