I haven’t a clue but our counter top brewer drips hot water into a filter containing 6 level scoops of supermarket grade coffee grounds (approx 6 level Tbsp) and then it gravity drips through the grounds and into the pot with a final yield of 12 cups. Never timed it but per cup its a significantly slower process than the Kurig Machine that used pressure to force the hot water through the cup holding the grounds.
My guess is the longer a given amount of hot water is in contact with the grounds the more flavor will be extracted from the grounds. As a result, the fast pressurized coffee machines require more grounds per cup.
I know for a fact that the fast brewing machines in a 7-11 or Wawa require a lot more coffer grounds per cup than a much slower home brewer.
For about $6 lb, Costco has a really excellent organic, fair trade Cuban Mayorga coffee. Not too dark, choclately notes and full bodied, no bitterness. My other regular coffee, Jim’s organic Ethiopian Sidamo runs more like $16 per lb. I love the Mayorga and the savings. Of course, my local roaster is more like $20 per lb, I believe.
The Canadian two-piece is pretty much a one-scoop contraption, as is the Bialetti and the smallest Vietnamese filter. I suppose I could put more in the cone and the larger Vietnamese filter.
But the ones limited to one scoop also limit the amount of water to about 6 ounces as well, so I’m not trying to make a pint of coffee from a single scoop. (I am reminded of my father, who used to make three or four cups of tea from a single tea bag. Child of the Depression…)