My input here:
First, chill out fellas. It's not worth making the TDR look bad.
As Rusty likes to say, "different horses for different courses". IOW, you need the right tool for the job.
It's pretty ridiculous to say that there's a design flaw in not offering a gearing option that makes the CTD rev less. One could just as easily say that my Nissan Maxima has a "design flaw" in that it will exceed 140mph in a nation where the highest legal speed is 80mph or less. After all, think of all the wasted "performance" that came by not gearing the car to spin 6K rpm at 75mph!
Sure, I've sometimes wished for taller gears for my truck. I rarely tow, and it's mostly a commuter truck. It's my right, and part of living in such a great country. But actions have consequences, and if you choose to use a CTD in a manner other than which it is predominantly used, then there are compromises you must deal with. I'm happy with them, as 2K rpm @ 72mph is ideal for me.
Faulting DC for not offering a gearing option for the CTD that makes it turn very low hwy RPM is like faulting Honda for not making a 900hp Civic. THAT'S NOT WHAT IT'S FOR!! DUH!
While the idea of using OD as a cruising gear and 5th as a towing gear appears to be a good one, it just doesn't work. Mostly because you then have to make the gear splits so wide that it sucks for towing, and you basically have an NV4500 with an added OD unit.
I don't know of anyone that loves towing with a 4500-- just remember the 2-3 split and you'll know why.
Yes, it would be nice to have options. But if you'll look at it objectively, you *DO* have options. They're called a 1500 or Tacoma or Titan or whatever!
Life is full of compromises. It's best to get over them and get on with life. Worrying about that which you have no control over is surely wasteful.
JMO