Data Point 1: SF has an ungodly number of picks, not all of whom will make the team
Data Point 2: Marcus Lattimore was the consensus best RB in the draft until he injured himself.
Data Point 3: Lattimore is recovering but not recovered, and likely to slip to the 3-5 range
Data Point 4: Frank Gore - who the 9ers drafted in the 2005 3rd round despite injury concerns - will be 30 in May.
Given all that, doesn't taking Lattimore at the end of the third, stashing him on IR for a year, and working him back in next year make perfect sense for San Fran? It's essentially paying some of this year's draft excess forward into next season, and getting real upside, too.