8 Drivers for continuity
Shipbuilders probably did not like to change a proven design. Ships are structures with a high degree of technical complexity in order to be able to cope with the high risks of sailing. Shipwrights only had their knowledge and experience to work with, a profession well guarded in the egalitarian guild system. It was not until the eighteenth century that geometric methods were introduced in Dutch oceangoing vessels (Hoving 2006).
Shipwrights in the sixteenth and seventeenth century probably had their minds set to local traditions of shipbuilding. It is suggested that social practices of shipbuilding in Holland were different from the practices in England. The Dutch shipbuilding process was more transparent and egalitarian, allowing for a high degree of efficiency, while in England the differentiation in knowledge between the master shipwright and ship carpenter was reinforced. The master shipwright in England already engaged in methods of geometric ship design, while his Dutch colleagues still worked with rules of proportion. (Adams 2003, 190). So socio-cultural factors may partially explain why the watership retained its medieval S-shape all the way to the end of its existence, as opposed to becoming a flat bottomed ship with side-mounted retractable leeboards at an earlier point in time. Rather to the contrary, the keel plank was replaced by a heavy keel beam at the end of the sixteenth century.
An important factor however must have been the unique quality of the watership design in itself, enabling it to absorb new functionalities. The stable and robust design of the watership probably made it the best local candidate for such heavy duty functions as pulling large trawl nets and ocean-going ships in the rough Zuiderzee environment. The S-shape of the underwater hull and the enlarged lateral surface area underwater must have made it a very manoeuvrable ship with a smaller drift component then could be expected from the flat bottomed ship. This was an important quality as for example ships in tow, losing too much headway in the mud of Pampus, would drift towards the sand bank near Muiden.