NFFF COMMERCIAL RADIO OPERATOR MONITORING WX DEVS IN SOUTH PACIFIC VIA B744 IS CONFUSED BY DATALINK COMS FROM B747-400 FLT CREW.

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AT XA40Z; WE RECEIVED A CLRNC FROM NADI CTL TO DEVIATE R OFF COURSE 50 NM. AT XA20Z; WE RECEIVED A CLRNC TO DEVIATE L 50 NM; BOTH DUE TO WX. WE ULTIMATELY DEVIATED R 30 NM. AFTER BEING CHANGED TO AUCKLAND CTL; THE NADI CTLR INQUIRED IF WE WERE DEVIATING AND WHAT DIRECTION. WE INFORMED HIM R OFF COURSE; 30 NM AND THAT WE WERE BACK ON COURSE AT THAT TIME. THE NATURE OF THE INQUIRY CAUSED CONCERN ON THE FLT CREW'S PART THAT WE HAD POSSIBLY RPTED BACK ON COURSE PRIOR TO INITIATING THE DEV. AN INVENTORY OF THE CPDLC ATC LOG INDICATED WE HAD NOT CANCELLED THE DEV REQUEST. THIS INCIDENT BRINGS UP CERTAIN CONCERNS OF CPDLC DEV CLRNCS. 1) UNLIKE BLOCK ALT CLRNCS WHERE WE CAN INPUT FLXXX/FLYYY; L AND R DEV REQUESTS CANNOT BE CONVENIENTLY ENTERED IN ONE MESSAGE. WE EITHER HAVE TO SUBMIT 2 MESSAGES; ONE FOR L AND ONE FOR R; OR INPUT ONE DIRECTION AND ADD TEXT FOR THE OTHER. I FIND THE LATTER LACKING AS MOST OF THE TIME THE CTLR DOESN'T READ THE TEXT OR UNDERSTAND THE REQUEST AND JUST CLRS THE DEV TO THE MAIN DIRECTION AND NOT THE ONE REQUESTED IN THE TEXT. 2) WHEN 2 REQUESTS ARE SENT CONSECUTIVELY DOES THE CTLR POSSIBLY THINK THE SECOND CANCELS OR OVERRIDES THE FIRST? THIS MIGHT BE THE CASE IN THE CURRENT SIT. 3) AS AN ASIDE WHEN A REQUEST IS MADE FOR A DEV THE CLRNC INCLUDES A REQUEST TO 'RPT BACK ON RTE.' THIS AUTOMATICALLY PUTS A 'BACK ON RTE' PROMPT IN THE ATC FMC PAGE. IF WE ASK FOR DEVS EACH WAY IN 2 SEPARATE MESSAGES THERE ARE 2 OF THESE PROMPTS. IS EACH PROMPT SPECIFICALLY RELATED TO THE MESSAGE; ONE FOR L AND ONE FOR R? CAN WE DELETE ONE AND SEND THE OTHER AND THEN CANCEL BOTH DEV CLRNCS OR DO WE NEED TO SEND BOTH?