They became unbearable when TV stations started airing them back to back, to the tune of 4 episodes a night. Then Fran, whom I liked, and her voice started grating on my nerves. The more episodes I watch, the more her acting becomes stilted and her "cuteness" has turned unbearable.
So I started focusing on Niles and C.C. I couldn't stand C.C. at first. Now, she's my favorite and I can't stand Maxwell anymore. He is the most stilted, wooden actor. I never bought their romance either way: he was always cold fish, limp noodle type. And there is nothing attractive about a woman (particularly such a gorgeous one who could have any man!) throw herself at such a boring fool! (Ironically, the same goes of FD in her private life!)
To answer your Q, the show jumped the shark when they got the romance going. But mostly because "Mr. Sh." put out no vibes showing that he liked Fran. At all. Ever!! When I watch it now, Fran comes across as so desperate it's embarassing. Particularly when you look at how life has imitated art. (She didn't know her husband was gay when she filmed this?!) Considering her name is the same in real life… it's even worse! (Why did they ever do that in the 90's?! Every woman had to have her show under her own name!)
And either her husband wrote Sheffield gay and secretly told the actor to act that way or he acted him that way. Either way, since I have the show on the background almost nightly, I've started noticing things: the amount of "homophobic" jokes = her husband telling her something (LOL!) but she totally missed it so he had to come out to her! There's 1 episode where Gracie makes faces mocking Fran, behind her. When you've read that Madeline Zima was treated badly by Drescher, you begin to wonder if that wasn't in the script, how come no one caught it. Etc..
¯_(ツ)_/¯
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