Complex sentence: He achieved the highest success rate in the history of ocean rowing, comparing the number of attempted-speed-records to successful expeditions, earning at least one of the most sought-after ocean rowing world records during each crossing.
Split into simpler sentences: He achieved the highest success rate in the history of ocean rowing measuring the number of attempted-speed-records to successful expeditions. Fiann earned at least one of the most sought-after ocean rowing world records during each crossing.