It was certainly a discussion point before I retired in 2008, where CMRs could be below 1800kg thus in theory requiring QRH action on reaching. I don't know if the issue has been addressed anywhere. The 'problem' only arose when the optional higher fuel state was introduced and as such in reality it does not constitute a 'crisis' since it
used to be 'ok' to fly around above the lower warning level without action - and the engines have not changed!
May I suggest a formal query to your airline on how they expect crews to treat such a warning during 'normal' operations. They might wish to consider making CMR 1820 minimum? ...(or not........
)