Should writers tailor their first page(s) to attract a request, even though the first page(s) may not mirror the rest of the manuscript in either tone or style?
I know attached pages should be stellar, but must the ultimate judgment of plot occur within 250 words?
Do you ever answer your own questions when you write them out?
I'm perplexed about why you'd think it's a good idea to change the tone or style of a book to attract readers only to change tone or style after the first pages.
I think there was a term for this: bait and switch.
You're making some erroneous assumptions here as well: I don't make a judgment about the plot from the query. I decided if I want to read the book (and that is the material I use to decide.)
The purpose of a query is to entice me to read the book. It's not to lay out the plot. It's not to introduce me to the world you've created.
Mismatched tone is one of things that sends me right to the rejection button. I see this when writers use a light breezy tone to talk about scary things (like shark fin soup.) Or a somber tone when talking about kittens.
As with many writers who are meticulous, you're over-thinking this.
Tell me what the book is about in the plainest, yet most enticing way you can.
It's really simple, but it's sure not easy.
And yes, I often realize the answer to something only after I've written about it.