I've always wondered why the New Yorker puts an umlaut on words with a double vowel, like coordinate or reelection. Reëlection just looks so weird. Also, it's not really nice enough to go sunbathing today :(

@1, more properly called a diaeresis (uncomfortably close to diarrhea and diuresis), when used in English words as you describe. Kind of fussy and redundant.

I know, I know. But the first time I ever really came across it was Ms. Slaven's German class in high school, so it's an umlaut to me.