Turbine's official Dungeons & Dragons Online website has been updated with a new dev diary that discusses the challenges associated with implementing a feat, skill, or special ability. A snippet:
The last challenge I'd like to mention is the most beautiful thing about D&D. the complexity of the rules. D&D has a rich set of rules that try to balance, complement, and empower players to make decisions that are unique and interesting. To accomplish this, an incredible framework of rules (and exceptions to those rules) exists. Several times a day, I reach for the Player's Handbook to look up rules, and I often find interesting exceptions to the rules that I hadn't anticipated or remembered. This naturally leads me to feel a little insecure about any sweeping generalized rules that we write in code from day to day. The question always comes up. what if there is some off spell, creature ability, or general condition that trumps this rule? I then find myself going on a great learning adventure trying to find the rule that balances this rule. So anytime I implement a rule, I need to anticipate and find the counterexample.