Not a bad idea.
Yes, but we already were talking about two things before: Absolute unit based (=dry) dose like in tablets, and divisible dose (=liquid). Now we are talking a third thing: the first derivation thereof. We haven't made those distinctions canonical, except when we want to calculate daily doses (e.g. for DOSE_ERA records). That's when we need the complex @Klaus-like logic. This will add to that.
We could try figuring it out. But won't be easy on the ETLers, because instead of just dumping NDC codes they will have to start getting into the detail.
Correct, but I would definitely not open the door for that. In contrast, in the long run we should provide means to convert. The conversation here is about what dose is actually given. Not how it can be differently represented.
That is the idea, @alexdaw. We will fix it.