Not to disparage, but just to make an observation, the "Hidden in Plain Sight" part of a lot of this is affected by the fact that there are too many "full cups", not only in Aikido, but many other arts, as well.
It's a waste of time talking to the people with cups that are already full..... but they're the same ones who came to dominate Aikido for too long and who put Aikido in a position where so many are saying "wait a minute.... something must be missing". It's not only Hidden in Plain Sight, it's Ignored When it's in Plain Sight.
All good Points Mike I don't think its just Aikido that ran out of gas. its everywhere. I have folks in my dojo who have trained with the parent art of Aikido-DRAJJ. Folks who trained with the best DRAJJ men in the world who will openly tell you most of the guys in that art...just don't get it. I've had people from DRAJJ look at me and say WTF? They couldn't explain me doing their art's waza better than most in their own art. They've recounted failing at aiki-age (peng jin) and being told "More work!" Then I actually use "words" and hands-on and help them to fix it. Not that I do DRAJJ- I don't. And I ain't much!!
If you recall Rob said the same thing when a Sagawa student -who was known- walked in to their class and he had nothing, no structure, and how that could be- when he trained with one of the best in the world. We were just discussing this over dinner last night after a seminar. That perhaps this emptyness is prevelant in all these arts. That and whether or not we were a contributing factor to this downward trend or it originated with teachers unwilling or unable to teach.
My guess is its a combination of all of the above. then again I know several Asian teachers who today, this very day, do not show the majority of students what and how to do the real stuff.