double clutching

Absolutely correct.

I think I told a story earlier about a conversation I had with my transmission shop. The guy, who has decades of HD transmission repair experience, agreed that a driver can float thousands of shifts but there will be a time when he blows a shift and that might crack something inside. Then a few weeks or months later, maybe when another driver is in the truck, the trans goes for a crap and the 2nd driver gets the blame.

So yes, drivers can float gears and they don't need to double clutch blah blah blah. They are not telling you the whole story. I've ridden with drivers who tell me they don't need the clutch and they don't grind. Well let me tell you they do grind and crash and bang...makes me cringe but they *think* they're good.

You might try getting a different perspective by asking this question in the Heavy Haul forum. Any monkey can float his way through the great plains with 20,000 in the box but the stakes get higher when you are on a grade with 100,000 plus.

$.02