What the fuck is bad dark roast coffee?
It is not the roast. It is water that is too hot for a bean that is already wide open.
Dark roast coffee is very porous. It does not need as high of a water temp to extract it like a light roast or a medium roast would. There is not nearly as many niche flavors hidden in a dark roast bean.
If you are using 205 degrees or higher on a dark roast, there is a very good chance it will come out ashy and burnt. Unless you like that. No judgement.
195 to 199 is the sweet spot. Some dark roasts will not be as dark as others, so that water temp can be pushed a little higher.
If your dark roast beans are extremely oily and almost black, use 195. Maybe 190 to keep down the ashy, burnt, and acidic flavor profiles.
Our dark roasts are dropped a few seconds after second crack begins. They are dark, but not too dark. Much more forgiving than something nearing charcoal territory. They still do not want 205.
You wanted damn good coffee. Not a second roast in the pot.
Pay attention to your water temps when you're brewing your dark roasts and notice a drastic improvement in the flavor profile.