http://www.cowboyszone.com/2012/05/is-nickel-corner-new-safety.html
You guys are cracking me up here. No coordinator worth his salt will run a dime or nickel defense as a base defense. Just as AbeBeta has pointed out in his posts teams will run the ball on you all day everyday until you can stop it. If you run blitz with more than 4 guys, someone is going to be uncovered and the FS (Sensabaugh who is not even pictured) is going to have alot of ground to cover for a 2nd and 2.
The above picture is an example of Scandrick covering a TE in a 12 personnel in a close ace formation - also called snugs. (Both TEs are lined up outside the tackles in a flex position. Rob Ryan countered a base personnel formation with a nickel defense because Travis Beckham is 6.3 234 lb TE who rarely blocks when he is in the formation or catches a pass for that matter. (4yrs/26 rec/264 yds/3 TDs)
Scandrick has covered TEs numerous times in these situations and the media has somehow translated that he nows plays safety as well when in fact he is just a slot corner doing what a slot corner does best and that is cover the slot receiver. Ian Rapoport did a real nice hackjob with his article and as Parcells would say "you guys got sucked".
Dallas is holding onto Jenkins for depth or unless a team gets really desperate and wants to part with a 2nd or 1st rd pick.