Yardstick, verses ability.
The technical yardstick of advancing for ranks of aikido is the viewing of technical ability. It is so contrary to the overwhelming moral majority who answered this question, the actuality that verses the morality is shown to be inverse.
Or, the real answer is that technical ability is the measure of students and teachers.
Teachers do not live with students, observe their daily lives, and how they react to different situations, they are human beings who spend an hour of so teaching then socializing within the week on a semi-personal level.
Hey, even a teacher needs space to be who they are, they are only human beings.
Our present measure of Aikido is based upon the technical expertise per level, and the ability of the student to observe levels of safety while practicing or testing.
So, even though our superfluous social lives brush as we practice Aikido, the true measure of what we will do when pressed is unknown to both our classmates or teachers?
Many of us, the older practitionersespecially, have some clue as where the line is drawn for us to cross and when/how we should respond to violence outside the normal lines of moral civility, but our passiveness is mistaken for slovinness, or inability.
This kindness, many of us show, is the waryness of lessons learned over a lifetime. This, with the understanding that the old ways of violence, are not always the best way to deal with most situations that can be resolved by words or simple lessons. Hence, Those of us who realize violence sometimes roam into areas of concern that seem of no consequence to the practitioner who believes that harder longer training is the answer to all problems. It isn't.
Aikido practice can be the ability to use common sense for applying the abstract ideals of religion, emotion, and lifelong goals that are diversely congruent to who and what you want from life today.
If finding completion of who you are is found in hours and hours of practice, then that is you. Don't press it into the lives and measure of what others expect out of aikido or the level of completion it gives to others who practice Aikido.
In many cases, the clumsyness of an older practitioner who is new to Aikido is the physical and mental restraints from using agressive/violent techniques from other MA practices. So, don't go getting all full of yourself because your five years or more of practice get the nod of your teacher and peers, and the older new students are drawing back ... it could be that many of us have had enough of hurting people and we seek another way to practice MA's ... Aikido?
Ramble on? Yep.
Aikido has many levels of practice, and many levels of expertise, some of them are not tested on the level of kyu or dan, but by the measure of how it affects our everyday lives or how it changes our more violent tendancys into acceptable social behavior.
The only test for this is how you live each day compared to how you lived each day before today.