Some of the rules I have always broken are never QTing, no testing, using ocean rock, allowing "pests" to live happily in coexistence with my reef, no dosing, no chemicals besides prime, no filtration additives besides carbon about once every few months to clear the water, and others I am sure.
My general philosophy in reefing has always been to create as natural an ecosystem as possible. I see the tank as the ocean, the refugium as the estuary, and the skimmer as the beach. I allow all life to live and thrive in my tank in order to fill its natural niche in my tank. I believe even things such as red planaria play a vital role in my system. By allowing everything to thrive in my tank just one thing will never take it over. Checks and balances.