"If the seahawks really have it together and understand how to utilize their talent, why would they limit harvins capacity? Injuries are a concern, but all nfl players have injury concerns. Maximizing the output of an offense usually revolves around putting the ball in the best players hands. Those two players are harvin and wilson for the hawks."
Considering ANY player to be the best player on a team is a very one dimensional way of looking at things. I think organizations that "get it" look at things in a MUCH more multi-faceted way. Its the next step of specialization that goes beyond the concept of single RB over the years becoming RB plus a 3rd down specialist. Its happening in every facet of the game and is only limited by the NFL roster size.
Its a very philosophical discussion better left to a different form of media but consider that teams should, and I think some do, look at the best player on their team within the context of which particular down and distance they are facing, at which particluar point in the game, and where the score is currently. Going beyond that the gameplan itself can be very defense specific and tailored to attack the weaknesses of a particular team based on idividual matchups IF you have the players and have built the roster in a way to accomplish that successfully. I personally think its a great improvement over the "line up and do what we do best approach" unless you have an AP or a Tom Brady but even in that case your season and franchise over the course of seasons becomes awfully dependant on a single or couple of individuals.
"Why would the seahawks invest in harvin if he was more of a certain situation/gimmick/diversion if he is obviously the best player on the roster?"
Now taking my comments above into consideration consider how Harvin can fit into those plans in a variety of ways. He is the ultimate Swiss Army knife player! Do you use a Swiss army knife for every situation that you encounter? No!
You probably could, and there is great value in having it available if need be, but if you want to open a bottle and you have a bottle opener you will probably use it. If you need to cut open a box and you have a box cutter your'e going to use it. Does having those other things in your toolbox which you use regularly mean that a Swiss army knife which you can always carry around in your pocket is not of great value?
The average fan and I think even NFL teams undervalue special teams play tremendously. As a Bears fan and watching them over the course of many years FBN I know you realize how important special teams play can be in winning football games. If you have a good defense ST plays can make up 20% or more of an individual games plays and assuming a low scoring affair based on that good defense a ST score or 2 can easily be the difference. You don't think having Percy on returns could be the difference in a few games between the 49ers and Seahawks over the next 5 yrs or so? Is there not great value in a player that can make the difference in a division championship and homefield because he broke off a punt return TD?
Again Percy can be used in the backfield to run the ball, to go in motion as a wideout to help Wilson determine the coverage, to exploit mismatches on the defense and having one player that can be used in so many different ways is priceless to the team but it does not mean that he will pile up FF numbers for your team. The Hawks have very sutiable players to accomplish each of those tasks already.
Not going to get stuck here and go on and on though some might say I already have. The point is that I disagree what you think Harvin's role will be. I also disagree that the role I envision is not of huge value to the Seahawks, but would still limit him from accruing huge stats to your bottom line. He WILL get touches and I can see where it could happen your way if the Hawks suffer a number of injuries (or suspensions) but my base case is that he will not get the opportunities of a Cobb or a Cruz, I am assuming PPR league.
Unless return ydg is a scoring category I would stay away at his ADP. TDs can be a volatile stat and that is certainly another way he could end up performing to ADP if he gets a bunch.