observation billing #3

Geez, this forum is getting my question wrong. The first question posted is correct until the end where I ask for someone to show me where it is written that it is ok to bill 99224-99226 for an est'd pt of the provider, while in observation. I found that this is written in the 2015 professional edition of the AMA CPT® guide book. There is nothing about this on the CMS website so, I'd like to know where the AMA got their information. Since Nov 2011, it has been the rule to code est'd pt E/M (99212-99215) unless the provider was the one who admitted the pt to observation status. Can someone seriously "in the know" answer this so I can train my coders correctly. Thanks