*Sigh*
Commisars make very little sense as written.
We know (from Cain's Last Stand) they are trained in intelligence analysis and various counter insurgent principles.
We know they must have some tactical training, since every commisar in the novels seems to be a highly skilled tactician - indeed they'd have to be somewhat familiar with tactics to even fulfil their jobs. Yet from their advancement possibilities, they are about as clever as a bag of rocks, and so only about 10% smarter than the average Ork.
Atleast they got fellowship instead of stregth, finally.