Description: http://www.edmunds.com/insideline/autoshows/chicago/2008/gmcdenalixthybridconcept.html We didn't know what to make of the GMC Denali XT Hybrid Concept the first time we saw it, so we asked Warrack Leach, the lead designer on the project, to explain it. He said it's an example of a "recreational vehicle done responsibly," a suspicious-sounding catchphrase if we ever heard one.