To further reinforce your points and Todd's, here are some words from George Lawrence Stone (taken from his Technique of Percussion column):But nobody goes from just learning the alphabet to write either War and Peace or The Cat In The Hat.
Which leads back to the original question "Is there any benefit in drilling rudiments for long periods of time?"
My answer would be Yes or No.
No - if that is all one does with them. Endlessly repeating "a a a a a a a a a a a a a a a a a a a a" before moving on to "b b b b b b b b b b b b b b b b" - there is no path IMO from doing that to writing anything. So it is with ONLY practicing rudiments - one at a time - slow to fast to slow. A perfectly fine exercise - and one that really does require much repetition to see the full benefit from.... but is only the beginning of the study of rudiments.
Just as schoolchildren, having learned the alphabet, then move on to grammar and vocabulary - so it with rudiments.
Rudiments are the basic components of most all drumming - so like we use the alphabet to create words and those words to create phrases. We do the same with rudiments. How?
Well with children, we don't just teach them the alphabet and then say... OK you've got the building blocks.... have at it. Read this book.. Write that novel. No we take them through building words.... making phrases.... step by step until they are capable of translating thought to paper themselves - in competent cohesive manner.
This is where the books by the authors Todd listed come in - as they are instruction manuals, worksheets and exercise books that take us from "See Dick and Jane" to reading Dickens and writing term papers. They are musical grammar books - that instruct us how to utilize our "alphabet" to make music. In this case, the music of the snare drum.
This is why I harp on teachers about this - why I say "if you are just showing students to play rudiments only as that play them repeatedly over and over again exercises (a a a a a a a a a a a a) then you really aren't teaching them rudiments". Only by tagging through Hard, Wilcoxon, then Podemski, Goldenberg, Peters, and Cirone are they learning to actually USE rudiments. Learning how to use them musically and thus, be able to incorporate them into their playing.
Certainly every player isn't going to make it though that whole list - but in my experience, anyone that hasn't chewed through a good chunk of it will have audible, discernible holes in their playing... holes in that vocabulary, in their range of expression. And as so much of this stuff is at the root of all of our playing - it will be recognizable.
Does this mean a player might not find their niche - where their limitations are not a hindrance? Absolutely they might. But it will be noticeable. And it will limit their range of opportunities.
So sorry - at least in my opinion - what Todd wrote was the furthest thing from being absurd.
My 2 cents
"A reader writes: 'A brother drummer claims that there are only two rudiments in drumming, the single stroke and the double stroke, and that these are all you have to know. Is this right?'
Yes, reader, it's right as far as it goes. Tell the brother there are only twenty-six letters in the alphabet, and that's all he has to know, until he finds out they have to be strung together in some sort of way before they make sense."