Why didn't they just put coffee grounds in a tea bag and sell it that way? It seems like it would produce instant coffee almost on par with regular drip. They might have to adjust the density of the bag's paper, but that's about it.
If you google "coffee tea bag" the first link explains why not: "Unlike tea leaves, coffee grains release little flavor unless they come into contact with water that is not only hot but also agitated. The water may simply flow through a sock filled with ground coffee, or it may be thrust up through a percolator, but it must be moving. This limitation has traditionally made brewing coffee by the cup messy and ineffici…
You are correct that you must "agitate" the water.. You have to stir it for a few minutes. I think it tastes better than instant coffee (which seems to have some sort of bizarre chemical taste, at least to me).