A blend is a compromise. An alchemist's approach to coffee in many cases. Taking parts, that alone can be quite inferior which equal something greater as a whole. Lead into gold, not quite, but close.
Of course I am pitching the extreme to prove a point here.
Espresso blends are historically composed of some of the lowest grade coffees available. Robusta, monsooned malabar, and low grade indonesians are the backbone of the traditional generic milk espresso blend.
What if you took a wine approach to blending? Two or three high grade varietals blended together for something even more complex. Instead of putting together inferior parts, use components that were great as separate pieces.
What if we took only amazing high grade coffees and were to blend them? Not to suddenly abandon the terroir view of micro lots and soil quality, but to add this blending on top of the great single origins/green quality concepts with one caveat to give the farmer due credit:
What if blends came to market that were transparent and labeled the contents and percentages proudly on the bag?
Abandoning the black box approach to espresso and stating what was contained inside for the consumer.
It's been done with percentages and all by the Danes.