Due to a known limitation in the geometry engine (https://community.esri.com/t5/arcgis-parcel-fabric-questions/update-cogo-is-changing-the-arcs-to-lin...) , COGO attributes can be inadvertently updated on a flat curve and the geometry is interpreted as a straight line.
By exposing the curve geometry in arcade (as well as information about the curve like radius), we could create attribute rules that protect and/or restore the curve information.