Here is a close shot of the adjuster mechanism as well as the inside piece that pivots. As the part rotates when the clutch cable pulls it, the shifting rod is pushed which in turn reaches all the way through the engine and pushes the clutch basket which releases pressure from the clutch discs. The adjustment sets the pre-load on the shift rod and will quickly remove any large amount of slack in the clutch pull. The cable collars on the clutch perch will adjust for minor amounts of clutch play which might be caused by worn pivots or stretch that might occur in the cable itself. This larger adjustment is used for installing a different cable or new clutch. Big changes in tolerance from worn out parts to new replacement parts probably would require this adjustment.
If you pull your clutch in and get resistance from the springs but it still doesn't dis-engage, first adjust the collar on the clutch perch to remove any slack. If that still doesn't actuate the clutch then this would be the adjustment to make.