[johnnyrod]

Doesn't matter whether you use the top or bottom cable adjuster, they both do the same job. As Adam says, the reach adjuster just changes the angle of the lever, doesn't move the cable, so you need to pull the lever by the same amount to disengage (so setting it to a smaller reach will set the biting point closer to the handlebar). As for gunge, yeah it's not uncommon. Cleaning chains is a waste of time though, even the manufacturers say so. As you can see, everything just flings off - they're self-cleaning because of the lube.