I've never understood why, but my BB7 always feels a lot stiffer with the barrell adjuster on the lever wound right it! I've set it up with the adjuster right in on the lever, then adjusted the lever pull on the red dials, but it was just mush.
Also, when I took my BB7 apart ages ago, I only had 1 ball bearing in the caliper, and saw room for another 2, so I found 2 the same size, and put them in too. The brake felt a lot more solid after that, as it was like the caliper was kept flat when pulling the brake, as apposed to it 'leaning over' on the one BB in there..?
Made sense to me anyway, and I think it payed off!