Theme:  Notice that 65-across ties everything together;  “Hidden” in a clue usually means that there’s a word inside the long answer that you normally wouldn’t notice.  Often this is a word that combines the end of one word with the beginning of another.  Often you don’t get any of the long answers until you get a number of crossing answers.

Specific hints:

Shortest paths:  well, STRAIGHT LINES doesn’t fit, but something very similar does.

Surfer girl:  Does it help to remember that what part of the 50 states has the biggest waves of all?  Well, this word comes from there.

Igor, for one:  …or: “Dog trainer?”

Slugger Mel:  If you didn’t know this one, check out Words Every Solver should know.  Very common puzzle name.

Baseball taps:  Well, I’m not sure it’s exactly a “tap.”  Anyway, don’t think to deep on this one, it doesn’t have anything to do with playing taps, or something like that.

How losses appear on a ledger & futile:  sometimes things are so bad it takes more than a word to describe them, well, approximately

Père  – a français king, évidement.

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