2006 Chevy Silverado 2500HD 4x4, 6.0L, with a 5 speed. I started floating them at 50,000 and I currently have 190,000 on it. I've driven slow. I've driven fast. I run a 1000 lb Fisher 8.5' XV2 in the winter. I've hauled over 20,000 lb with my dump trailer. I've towed skidsteers, backhoes, mini excavators, and anything else you can think of in the dump trailer. I even float with a load on the truck and yes with that 20,000 too. In your infinite wisdoms, I would've left my tranny about 100,000 miles ago. It's still going just fine. I think there's a bunch of you scared to try anything or just incapable of doing it. If you truly think it's bad for the gears, prove it other than your opinions.
I maintain my RPM's better through shifts. Consequently it's less fuel used to build those lost RPM's back. Unless I'm rough on the old girl, she doesn't make a noise in the tranny. I don't see the point in this double clutch talk. Sounds like a transmission guy's trick to wear your clutch out sooner. It's about like wash, rinse, repeat.
If it wasn't need, why'd they put it there? That's your logic? Even floating, it's still used. Starting, stopping, switching directions. You will need the clutch. How much stuff is on your current vehicle they added but you don't use?