For me, "really deep" is a mix of a returning upperclassman (with experience in the system), the heir apparent (with experience in the system), and young guys who are learning the system and/or just joined the team. BYU currently has a bunch of guys that "could" carry the load, but there's a complete lack of experience and proven track record. There's reason to be optimistic, but let's not overstate things. The RB situation before the grad transfer was looking really rough.