Here's the executive order: http://www.whitehouse.gov/the-press-office/2010/12/27/executive-order-recruiting-and-hiring-students-and-recent-graduates
No matter what the wording was, the real reason this came about was that certain groups, including veterans, charged that agencies were using SCEP and the other programs to circumvent the traditional hiring rules (they weren't wrong).
(My wife is in federal HR)