A self-learning and/or self-adjusting communication controller and/or optimizer uses operational data collected from a communication system to adjust operation of the communication system to changing operational, environmental, etc. conditions and, in some embodiments, to customize operation of the communication system's lines and components so that their performance can be controlled, improved and/or optimized. In various embodiments, operational parameters and/or rules are established and/or adjusted based on information obtained from the system concerning the system's operation; information regarding margins used by a DSL system and code violation counts reported by the DSL system are used to set margin levels for one or more line sets (each line set including an individual line, a group of lines, a binder, etc.) and/or other users and/or components of the DSL system; and, the controller and/or optimizer forces a small number of test lines into as yet un-experienced and/or unimplemented operational conditions so that new knowledge can be obtained.