Complex sentence: Some historians believe they may have carried the heaviest-armoured knights of the European Late Middle Ages though others dispute this claim, indicating that the destrier, or knight's battle horse, was a medium-weight animal.
Split into simpler sentences: Some historians believe they may have carried the heaviest-armoured knights of the European Late Middle Ages. Others dispute this claim, indicating that the destrier, or knight's battle horse, was a medium-weight animal.