Brain Bag owners have all been cheated. Tom Bihn has been selling these backpacks to innocent people in order to test their miniature black holes that have been produced in their underground research facility in Seattle, right below their manufacturing building.
In all seriousness, my new Brain Bag arrived and it is about 20% smaller than my old North Face backpack and holds about 60% more stuff without breaking a sweat (if backpacks could sweat)
The only explanation is a miniature black hole that is put into the bag before shipping. It's also the reason they have to put excellent stitching and quality fabrics into the backpack - or else it will be torn apart by itself!
Although I don't like being cheated, I do like this backpack. I forgive Tom Bihn.