Hi Brian,
Didier Laine was a printer/editor. Hence the many books he published on the subject. All drawings you see in his books were from his hand. I met him in the early 90s' as I was starting collecting. He lived in one of Paris greatest areas (the 7th; his apartment was facing the former Ministry of War, on the front of which the first flag taken to the Germans was proudly exhibited in 1914). He was a very distinguished, always impeccably dressed gentleman (typically "Vieille France", if you know what this means...). He immediately offered to be my mentor, at difference with other collectors who often only showed disdain and contempt for beginners (fortunately it does not go like this on this forum). I started spending time in his office, each wall of which was covered with glass cabinets containing the collection. We would discuss the next Kube auction or a helmet I was interested in... I learned a lot with him. He knew everyone in the field, the crooks, the fakers, and of course the great dealers and collectors in Europe and the USA. His advice were precious!..
I think he started collecting in the 1960s'. Enlisted helmets then exclusively officer's. He would rarely purchase anything, considering his level of exigence, but I remember when he proudly put in my hands this fantastic Mecklemburg general spiked helmet - a unique piece - he had been coveting for a while and finally bought, not very long before he passed away.
Bruno