Doesn't a woodpecker's tongue also play a roll in protecting it? Or is the just a myth?
The tongue may still have an effect, but a different study methodology would be needed in order to test that theory.
Now I'm wondering how that's gonna work. De-tongue some woodpeckers and see if they get concussed? There's not any imaging that would work for this is there, where we could paint or inject their tongue with some dye and watch it flex inside their skull? that'd be a lovely video if it could be made.