You make a good point with the issue of transferring the trains off, but the only time I have ever seen water dummies on Fury was back in early March when they ran the ride for the very first time of the season. The water dummies are actually quite heavy, so they had to drain them out, which took quite a while, before they could pick them up and take them back downstairs. There is no convenient place to store them without causing a safety hazard to employees or guests because they'd just be in the way. A lot of people throw up on Fury. Not a day goes by where we don't get a protein spill. We may have to send an empty train for that, other bodily fluids, a computer error, etc. And because the water dummies were either drained out or completely out of reach, we will be forced to send out an empty train.
Yes, nitro has the hard nylon wheels on it. Fury cannot run those wheels, because it will speed the train up too much. Fury only has one trim, which the trains usually just fly through. If the trains continuously make it to the block brake too fast, the ride will eventually shut itself down, which it already does with the soft polyurethane wheels on it. Also, Fury was desgined to regularly run with soft yellow wheels. Had it been designed to run with the hard wheels, it wouldikely be open along with Afterburn, which runs the hard white wheels all season long.
Although Fury's opening day was in the 30's in the morning, the ride did not run until it hit 40 degrees and neither did Intimidator. Afterburn and Vortex, being older I don't believe it is a Carowinds thing, but a manufacturer thing. On the last day of Scarowinds, both Fury and Intimidator had to shut down early because it dipped below 40 and maintenance said the trains would've valleyed when we sent the empty trains out at the end of the night had we kept it open. Fury and Nitro although made by the same manufacturer, are different. No ride is exactly the same!