The draft strategy of Best Available Player is often a qualified strategy if used at all. Most NFL Teams will say that they will draft the Best Available Player because they are trying not to telegraph which player that they believe is the most valuable in their area of need.
Using the Eagles as an example, if the Best Available Player at pick 28 in the 1st round were a QB, how many people would think that they would pick that QB to give McNabb some competition? The fact is that they would not.
The truth is that only the most elite teams with few glaring needs have the luxury of using the Best Available Player Strategy and then they will do so only when they believe that they will not risk ignoring their areas of need. The Eagles who have a high need at CB will definitely pick a CB in the first 4 Rounds regardless if that player is the best available at the time or not. The Eagles have a high need for depth at LB also. They will likewise almost certainly pick a LB in the first 4 Rounds.
What does this mean in terms of Draft Strategy? The reality is that most teams will draft for need in the areas of high need. Once they believe that that need can be relieved, they will use their additional picks to draft the Best Available Player. This does not mean that the Eagles will necessarily pick a LB and a CB in the 1st and 2nd Rounds and then start drafting the Best Available Players. If the Eagles are comfortable that they can get the CB, as an example, in the 3rd, they may use the 2nd to pick the Best Available Player in that Round.