I think the theory on using mechanicals for birds is for a couple reasons. It's a small target(the vitals) so they use a broadhead that truly will group with your fieldpoints. If you can hit quarters or nickels at 20 yards so will most mechanicals.. over and over and over. Secondly, again because it's a small target the wider cutting diameter mechanicals give you that extra edge that may just put the bird down... so again... why not. Sure your regular broadheads are fine... but a lot more people (a.k.a. experts) are suggesting wide cutting mechanicals for turkeys for the reasons above.