I understand the sentiment about hard earned knowledge, it’s a common and age old one. It also stands in the way of progress. I believe that if people are posting here, all the side projects are public domain, being published by the makers’ own postings. Wayne started this with his personal genius, and deserves the pay wall as a small personal benefit.
The group of enthusiasts is small, as Steve U says, literally one in a million. In science or engineering full concise disclosure is the accepted standard so that solid progress can be made. I expect very few people will be taking up these ideas anyways, as long as petro is available. Mostly the information would serve for the advancement of members. Given that the information is already in the public arena, it isn’t patentable, so taking advantage of it would be on an individual scale.
I think the net effect would be to advance the art amongst the enthusiasts.
Also, the best defense against others claiming intellectual right to creative works is to publish it first, end of controversy.
Regarding precision of drawings, I feel accuracy is key, small differences in dimensions can cause very different results. Besides, it’s far easier to read a dimensioned, cross sectional drawing. Precise drawings will also be an invaluable resource for figuring out design parameters when coupled with operational characteristics. As is known even with the Imbert tables, and near 100 years of experiments, sometimes it’s still more witchcraft than science and design. Every successful working independent design is a wealth of information that advances group knowledge.
As a compromise, perhaps members would be more comfortable if precise final drawings and performance characteristics were kept behind the pay wall?