@Decaturbeginner: Whithout glazing you wouldn`t see the interior
Thank you for commendation
@John: Maybe the tradition of waterline models in Germany has its origin in the early years of Wilhelmshavener models in the 1950ies and in opposite to Schreiber models. By that time these models were often built by children to play with and it is much better to play without the underwater ship as I personally can confirm from my childhood in the 1970ies and 1980ies. I built lots of Wilhelmshavener but none of Schreiber even if the ships cemetry still existing in my parents house shows that papermodels aren`t really made for playing in general... Constructions have developed since than and so it seems anachronistic to you. Waterline models still have advantages in use for dioramas.