He's in his early 40s and has two decades of development experience. Experience is not the issue. The issue is his lack of machine learning knowledge. His dodgy, non-working, memory-hoggy misimplementation of A* search on a problem space of size > 10^20 demonstrates that very pointedly. Also, his general experience should teach him that if he knows nothing about a topic then he should do his homework. He doesn't. Education is key.
He sure can build a great ecommerce system in Rails though.
He sure can build a great ecommerce system in Rails though.