Many, if not most teams use clusters for their draft board.   If a player is in a cluster with the highest remaining player on the draft board,   often in that situation a player with a lower grade is the draft selection if he can fill a greater need.   Of course the size/ range of the clusters differs from team to team and are subjective.   Hence,  even if one team graded each player the exact same way as the other team,  team 1 might consider a player a reach but  team 2 might not.

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