There were a lot of changes made when Jim Harbaugh came to town, but one thing he left from the blemish of the Singletary Era was the banner in the team facility that reads, "Iron Sharpens Iron." Harbaugh likely believes this very same motto and has brought in competition to fulfill that motivational tactic.

The notable new additions to the team are Randy Moss, Mario Manningham and Perrish Cox -- two wide receivers and a cornerback. This is probably due to the fact that Harbaugh is trying to improve on both the passing offense and defense. Carlos Rogers has also returned, which should make this a talented and relatively deep cornerback group.

Moss and Manningham are playmakers with the talent to really push the defensive backs in practice, and ultimately make them better players. They are two completely different wide receivers, and by mixing and matching them with the 49ers cornerbacks in practice, San Francisco's secondary should become much more versatile and skilled in coverage.

Moss and Manningham will also light a fire under Michael Crabtree, Ted Ginn Jr. and Kyle Williams. Everyone will be fighting for time and this friendly competitiveness will act as Darwin's theory where only the strong survive. Harbaugh is trying to weed out the weak links and make this team strong at every nook and cranny.

Given how the 49ers free agency went, they could look to add in the trenches since it's basically gone unaddressed thus far in 2012. The offensive line could always get better, and many are talking about possibly bringing in the heir apparent to Justin Smith; though I don't think it's quite time yet.

But in terms of running the ball and stopping the run, the 49ers were pretty well set. They had a good group of guys on both sides of the football taking care of that in 2011, so they could still look to add more offensive pass catchers and maybe another safety in the draft to beef up the competition.

The frequently talked about prospects in regards to the 49ers have been Stephen Hill and Coby Fleener. And they could add one of them potentially, in order to both create competition amongst the receivers but also provide a greater challenge for the Niners defensive unit in camp and practice.

The chain reaction continues: because with more weapons, Alex Smith will be able to get the ball off quicker, which will make the defense have to find ways to get to the passer even faster. The pass rush would improve with a better passing attack brought to camp -- something that needed improvement when Aldon Smith wasn't on the field.

With a faster, more aggressive pass rush, the offensive line will have to get tough against the league's number one defense. The new additions and subtractions that happen this offseason are all for a reason, and it is ultimately for the betterment of the team. THE TEAM, THE TEAM, THE TEAM.

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