mobius In my experience, smokiness tends to be associated with the finish and is a good indicator of the coffee having been roasted darker, so you’re really just picking up burnt flavours (not necessarily bad, think about how barbecued food tastes).
Similar to smokiness, are those dry, astringent, metallic notes that are sometimes present. This can occur in over-roasted coffee as above, or in over-extracted brews, but you’ll also see some of those flavours in some varietals, especially those bred for disease resistance. Again, the flavour is usually present towards the finish.
It can be a bit of a process of elimination to figure out what is behind these kinds of flavours. e.g. if they’re related to the extraction, they’ll disappear if you extract less. If the coffee is clearly not dark roasted, then it’s likely to be the varietal.
Like with a lot of things, some bitterness is good - dark chocolate? - and like salt in food, it can be conspicuous when absent! Again, all preference - some people like more bitterness than others. Then we’re back to how these things are described. A dry, short, slightly bitter finish may be described as ‘black tea’ - the coffee doesn’t taste like tea but it’s a quick and easy way to describe the finish - or maybe the roaster will draw a comparison with the tannins in a red wine or something like that.
