This is something I've wondered about. I have noticed that this rule is more honoured in the breach than in the observance. I think the rationale has been that it would be practically impossible to redefine our coordinate system to something other than NED. The downside of always using the full enum text is that in cases where the UAVO name + field name is long, some equations can become very difficult to read.
 
Comments? @peabody124 I know that you code a lot with [0], too. What are your feelings?