I think many are misunderstanding. It is a board FAQs for the most frequently asked questions. Not a 100% guide. If you have suggestions to add additional information, you are more than welcome to add in pertinent information to the topic, if not I will take your suggestions and add them in. Especially if we see repeat topics. One of the major reasons why I went into so much detail for the Season 3 Ranked system was because of the numerous topics that were posted on the same thing.
Anything below tier 3 runes are never used once you purchase a full set. As such it is wasted IP. If you are below level 20 you do not need runes.