As stated above that "some" believe, this is not my personal opinion, but P. Maccus surely proves the point that the neglect of wood in the diet has no adverse effect on the fish's health as seen in many aquariums where wood is not used as long as the the diet is stabilized (highly fibrous).
My opinion is exactly as stated
In the article he does state that it took 18hrs for the bolus to move through the digestive system, whether this is effected by the type or grade of wood would of course require more information but seems to of course make sence.
Im aware of the many loop holes his work shows and how much more is required, but the aim was to show the point how little the wood provides nutrition wise.
I agree 100%
As for "Darwinism" i don't believe that the reason for the teethe was aimed at the wood but more the bio film and aufwuchs within, and that this was an adaptation in order to reach that food source, this also raises the possibility that the wood over time has become a necessity to the digestive system of the more exclusive species of wood eaters.