As a professional course developer I appreciate the chunking of the content into small easily to consume sections. The use of graphics and audio aided my learning greatly. The material was well organized, though could have been shortened some where content overlapped modules. The quizzes were generally very good though I found some answers didn't require mastery of the content. Writing of good quiz questions that are valid and test mastery is harder than most think and it wasn't well done in the course with some answers very obvious. Overall all great material - I would refer to again to refresh myself on various components in addition to spending more time on the water. Well done.