The list of fighters who became punchy is as long as my arm, it would be easier to count the ones who didnt. Most, at some point, exhibit signs of brain damage.
Are there typical stages for those that are affected. Terry Norris does sound terrible and it is hard to try and listen, but he seems lucid and that he understands. Is this, along with some of the motor skill impairments, just the first stage in what will likely get a lot worse?
Nobody is disputing that. Punch drunk implies frontal lobe damage. Parkinson's implies cerebellar/substancia negra damage. Two completely different conditions that can result from head trauma.
With Parkinson's, there's motor impairment which screws up speech. The speech centers of the head are intact. With pugilistic dementia, the speech centers in the brain turn to mush, so it's a higher order problem.