So, here is my loooooooong explanation and analysis! If you want the short version, it's here:
"Those words are fit for a queen!"
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Here's the long version:
The other users have noted that the speech they use in "Jeeves and Wooster" sounds old and outdated; that is why it sounds strange even to our ears (especially to those speaking American English like me).
Here's what I think:
First, we have to understand that the TV show involves some humorous dialogue, in order to be entertaining. So their dialogue is more theatrical, staged, or scripted. I think that is what we have in this instance here.
So, in the car, before they step out, Jeeves first says "With Miss Wickham, sir?"
We can tell from his tone of voice and by Bertie's response that Jeeves is not really asking "Are you in love with Miss Wickham?" but really "Why would you be in love with a person like Miss Wickham?"
Bertie then says, "No need to say it like that," and later asks "Just what exactly is your kick against Miss Wickham?" I think I have to translate this to understand it myself! I think he means "Just what exactly do you have against Miss Wickham?"
Then, Jeeves starts a sentence, saying "Well, sir, although Miss Wickham is a very charming young lady--"
And then here's another bit of humor, which you have to take into context.
Jeeves hasn't even finished his sentence yet, and is saying "...although Miss Wickham is a very charming young lady"--so we know that he is about to say something contrary to "charming."
例えば、「優しいことは優しいですけれど。。。」Indeed, later we see that he calls her "frivolous," and says that "Whenever l see Miss Wickham, l know that trouble cannot be far behind."