The author is overall pretty inconsistent with his story vs organization thing. During the first few books organization is king, now story is.
It was never explained how the dwarves could win against drow, who can basically solo armies. And those werent even top tier drow.
Its never explained how black could win a war against callow when hanno alone can turn a loosing fight into a massacre of a fifth of blacks troops and get away. Cavalry charge through mountainous choke+minefield into prepared infantry and crossbowmen, no less.

The story just isnt very solid in those aspects. It does gloss over too many things.