Cam Johnson and 49ers' draft planning

The San Francisco 49ers exchanged a 2012 seventh-round pick for 2013 fourth- and 2014 seventh-round picks Monday. That sounds like a pretty good deal and it's typical of the 49ers maximizing value. No one went into the 2013 draft with more picks than the 49ers possessed, and already San Francisco could have as many as 13 selections for next year.

The most recent accounting looks like this: 49ers outside linebacker Cam Johnson, a 2012 seventh-round pick coming off an impressive preseason, goes to the Indianapolis Colts for what is reportedly a 2014 seventh-round pick. Receiver Chris Harper, drafted in the fourth round by the Seattle Seahawks this year, goes to the 49ers' 53-man roster from the Seahawks' practice squad. Trading Johnson to the Colts made room on the 49res' roster for Harper, which is why I included the Harper signing in the equation.

Johnson probably would not have factored on the 46-man roster for games. Harper might not, either. But receiver is a position where the 49ers have long-term question marks. Anquan Boldin is signed for 2013 only. Michael Crabtree remains sidelined by a torn Achilles' tendon. His longer-term contract situation remains unsettled. Mario Manningham may or may not factor longer term.

Harper is intriguing at 6-foot-1 and 234 pounds. He shares height-weight similarities with Boldin and former 49ers tight end Delanie Walker. It will be interesting to see how the 49ers use Harper if he sticks on the roster for the long term.