I have also run across this problem. It would also be nice to have an option to transfer the new COGO attributes to the older curve value for the adjacent parcel (assuming they are supposed to be the same). Another thing is, if you are joining one single unbroken curve to several smaller curves from multiple adjacent parcels, it would be difficult to get a proper gapless join. There may be a need for a new workflow around this problem.
Justin McCulloch
Wood County GIS