lol derp i confused myself into thinking we traded up for a 3rd and gave a 4th
Even so, that link isn't gospel. It's numbers based guess work. It's not perfect, and you can say this trade offers more value based on our calculations, but until the production is determined on the field, it's speculation based on an assumed value of talent.
Even if it is a good system, there is no way that it could be applied to each individual team. There are too many moving parts, and teams will evaluate value based on their particular situation. I'm sure both the Browns and Steelers think they are getting what they want out of the trade or they wouldn't do it.
Winners and losers aren't determined at the time of the trade, but after the production pans out. It's easy to say, "Holy shit, Redskins traded the farm to get RG3, and they lost that trade." but if RG3 produces and the picks they traded off are irrelevant, then the Redskins come out ahead. Meaning hindsight is 20/20, and trying to project in the future isn't always accurate.