Do you taste it that way? I don't....
Sometimes I run a shot of typical length, and then slip a second cup underneath the spout to capture an extra five seconds of extract. What I taste in that final portion is a dilute caramel sweetness, along with an underlying note of something akin to creosote. The coffee flavor wheel lists creosol as a "bitter/pungent" flavor. But to my taste buds, if this creosol is a bitter flavor, it is a very mild bitterness.
Again, speaking for my taste buds, running the shot too long dilutes the flavors, reducing body and intensity. Sometimes I find the dilution and added caramel opens up the flavors and makes them more accessible, other times it just dulls them. But making the shot bitter? Not for me.
Comments?