H2O:
OCP for the feeder at the source protects the feeder.
The install you describe as I understand it is a 100 amp feeder to a sub panel with 100 amp OCP, which is code compliant.
The 200 amp CB in the sub is only functioning as a 'switch' (although expensive).
Some, but not all HI's are not the greatest at electrical code compliant determinations.
