First off if you really want it to be dead nuts accurate you need to run the battery analyzer. Batteries lose capacity as they age and also depending on the load they are under. Bigger load, less capacity.
True, and writing down the starting watt hours and the ending watt hours and subtracting them is doing what the battery analyzer is doing. And yes, usually the bigger the load, the smaller the capacity. But it isn't always true of all manufactured batteries. Some actually have more capacity at higher loads. It depends on the chemistries. And yes aging also takes a toll on capacity as well as heat and temperature they are stored at. Here is a great video about all of this.
Secondly while the DNA200 does mainly use the watt hours for the battery bar/meter. It uses that in conjunction with the discharge graph. It would have to because someone could put batteries in that were only charged to 4.0v. If it didn't also use the graph it would be off. What I believe happens is when its been at rest a certain amount of time, the chip compares the voltage of each cell to the graph and adjusts the bar if its off.
True, that is why Jim's battery bar jumped by a huge amount. Heck just today I had my Hotcig DX200 plugged into the USB checking a few things and I swapped lipo packs with a charged up one and the battery bar stayed on empty. It didn't show full until I unplugged from the USB and disconnected and reconnected the lipo. But it would have done it on its own once it checked the discharged graph again. I just didn't want to wait for it.


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