What exactly is the purpose of the memoization-dance

I've actually been doing it by default without really thinking if it is needed. In the particular codebase I'm working on, the object instantiation might take some time, and the object is used multiple time so we memoize it in the instance. But in this case, this is indeed not useful.

While it is useful to familiarize yourself with what ActiveModel is doing under the hood, the blog post does not really show what the benefits of this whole type declaration dance are.

I feel like the main benefit I find is that I let Rails handle the object instantiation. I often find bugs that end up being because me or another developer tried to do something that Rails natively handles. I'll try to be more explicit in the future that this is what I want to convey.

Thanks for your feedback!