I think when learning, asking the question "why?" is very useful.
If I ask myself and understand why I do something I am more likely to remember it in the future and apply it.
if a student watches an instructor do an irimi movement, they tend to see the instructor just move forward.
When they understand "why" he moves forward then they are likely to also see the distance that is covered and how close to the uke the instructor is.
When we watch or learn things we filter the information into a frame of reference that we have, based on our own limited experience.
asking 'why', instead of taking it for granted, removes our assumptions and allows the student to build on the new information.
so... I guess that was the long way of saying, if I wanted to teach someone to learn how to learn aikido I would recomend they questioned each part of the movements and understand why their funtion.