They are indeed important learning tools. The exercises involving pushing, pulling, lifting and compressing when practiced with progressively increased applied force allow the student to directly experience the principles and strengthen mind/body coordination. All the partnered exercises can be performed both statically and in motion.
good points, recently my teacher was saying that there is no difference between 'ki development exercises' and aikido, they are the same thing. Aikido is myriad of dynamic ki development exercises. And this from someone who spent the early years of his practice doing very martially effective aikido.
The problem, I think, is that most people only experience the demonstration mode of the exercises, which makes sense since the're generally not taught outside of Ki Aikido (and Ki Aikido offshoot styles). The exercises are therefore seen as tricks to wow the audience while their applicability as development tools goes unnoticed.
good point, also.