This post maybe long overdue but according to a good rule of thumb, when using phonetics. Initially, it best practice to say each letter individually as stated on the FCC Data Base, can't really say on the paper license received in the mail, since the FCC has stopped sending actual license documents.
The reason for phonetics is to confirms one's call-sign when you or the person you're specking to didn't hear your call or you didn't hear their call. This is more common on Amateur Radio Bands, because a lot of newcomers haven't really listened to Amateur Radio or GMRS before the got licensed. For FM simplex and HF, you gone to want use phonetic, after all, you're not going through a repeater and that line of site is always in your favor.
Heck, I know at one Amateur Radio Operator who was new, that he ided every time before unkey.
I'm guilty of this as many others, when signing off or 10-7. The last thing you say, should only be your Call-Sign. Not This WQAI363 going 10-7!
I'm 10-7 WQAI363