As pointed out by @Genava55 on the forums, 0 A.D.'s rotary mill is historically problematic. This patch therefore deprecates the structure, and instead introduces a special technology (town phase, workers +10% grain gather rate) for the Gauls, to reflect the fact they invented a harvesting machine in the Iron Age.
- Group Reviewers
Restricted Owners Package (Owns No Changed Paths)
Check for mistakes, agree this is an improvement.
About the cost of two rotary mills.
The rotary mill aura granted a 25% increase, but is local and temporary (only works as long as the structure isn't captured or destroyed).