 However, the French were inexperienced, their ships badly designed and co-operation with the English plagued by suspicion.While Dutch numbers were further reduced by Friesland retaining ships for defence against Münster, better training gave them operational equality.In the battles of 1666, the Dutch were hampered by lack of familiarity with their new, much heavier, warships, the complex federal command system and conflict between Michiel de Ruyter and Cornelis Tromp.