I can also imagine that someone with a lot of practice might be significantly faster than some unskilled researchers.

I also don't think it rules out it being something for a child. It's not so rare to do big projects for you kids even today, over many evenings and weekends. And when you don't have any books to read or screens to watch...

Ya, I tend to agree. I think I personally have spent 9 weeks of effort on gifts for 2-3 people in my lifetime, and I don't even have kids yet.

It could also be passed down through multiple siblings and possibly generations. And possibly the creation of it was itself a pasttime.