He does sound like an interesting person. I think the mid-14th Century was around the time when the vice and the draw plate were being spread around Central Europe by journeymen in the metalworking crafts. The draw plate in particular made life for mail makers much easier. They also started making very fine linked (and sometimes also heat-treated) mail for “civilian” use by courtiers and burghers (particularly in Italy) and these were very expensive – often more expensive than plate harness. So maybe he was able to find some useful profit margin after all.