Mountain Dulcimer Fret Variations | What do I need?

I’ve gotten MANY questions over the years about this topic. So here’s a video that will hopefully answer most of your questions.
I tried to be in-depth without being too boring, but it’s a tough balance for sure.
I’m positive I said something incorrectly in this, but I hope you will allow me some grace in that I’m doing the best I can.

All 4 of the mountain dulcimers in this video (for those who will ask) are Folkcraft dulcimers. 2 are Folkcraft - Folkroots models. 3 of the 4 are off the shelf models and the chromatic is a completely custom one with my name in the sound hole design. If you’d like to look at what they offer - https://www.folkcraft.com/?ref=2cb8sb... . That is my affiliate link (which means you pay the same price, but they will give me a small commission if you purchase through my link). By the way anyone can be an affiliate also.