Our words in the English language for reading and spelling are phonetically reliable. Reliable in the sense they do follow rules and patterns on a regular basis. Reading is 95% reliable and spelling is 85% reliable. - Dillon, Sandra (2005 revision). The Structure of the English Language. Albuquerque: SIS Publishing.
Our goal, as literacy teachers is to teach those rules that are reliable for reading and spelling, so that our students can accurately decode words to increase reading comprehension and accurately spell words to increase writing fluency.