dfk41 I tend to think that this is one of the things that people worry about, for the most part, unnecessarily.
Sure, I have heard accounts of blends mixed post roast, where one component had an under-development issue, but for a nominal roast, it seems unlikely to be a common issue.
Most espresso around the world is blended, sometimes up to 9 different components. If blends were so sensitive to the balance of the different components, how could anyone brew consistently? Wouldn’t 8/ 10 customers have an issue with their coffee?
A typical bean might weigh 0.18g, so that’s a hundred beans in an 18g dose. Given that beans of one of the components will vary somewhat, likely dove-tailing with the other components, surely you would need a bizarrely large discrepancy to really throw things out?