Maybe so, if you're dosing from the bag of shake you bought behind the bleachers off that guy who drives a brown pinto and once hit on your girlfriend.

but in California, for example, I could simply just ask the doctor writing my cannabis prescription what's their dosage suggestion based upon the medical reasons they were writing my presciption in the first place.

And it would mainly be a guess on the Doctor’s part as there isn’t enough science either way. Expect that to change in the next 10-20 years but at this point, your doctor, even with all the medical degrees behind them, know just as much as the bud tender behind the counter. Compound that with the fact that cannabis affects everyone differently then it all becomes a subjective mess.

I was fishing for "1 drop per day in the morning of $SOME_TINCTURE". My questions could have been phrased better.

But you're not wrong. If you wanna figure out what works for you, you'll have to experiment for yourself without a medical professionals help. That's true for any over the counter (OTC) medication in your local pharmacy, too.

Cannabis dosing is so particular to the specific tolerance level, brain chemistry, and body mass of an individual, that it's impossible to give any kind of general advice. Especially given the massive variation among products, even if they list the same milligram dosages.

The best guess I could give you for a "minimum therapeutic dose" for THC/CBD would be 5MG. Start from there and move your way up to what works for you.