What happens on a 200K when you don't have low enough gears?
What happens on a 200K when you don't have high enough gears?
If you are too dim to choose correct gearing because of the length of the ride, you are too dim too choose gearing in any case. Again, if you can't get it done with 16 or 18 or more ratios - then give it up.
And this goofy - super, wide range cassette or crank deal is just another "all -day" head ache to sort through.
There is a reason bicycles come with given gear ratios - and I guess - it must be so lame riders can guess about wider, more useless gearing setups.
End of story, eat turkey - go buy worthless gearing.