OK, so imagine this. There is a guy, let's call him Smith, who is the CEO of a large company. One day, he picks up an English tranlation of Musashi's Go Rin no Sho and decides that the martial arts are very applicable to business. So much so, that he decides that he needs to learn Aikido himself.
But Smith is a busy guy, and also very wealthy, so he decides that he's only going to take private lessons, twice a week. After all, he can afford it. And that way he will learn as fast as possible.
Let's assume that he has sought out Cindy Moore's teacher, and so Cindy, or Janet (when she's visiting the dojo), or another student, will get to be uke for the entire hour. At no charge, of course. So Smith never has to take ukemi. Smith doesn't even have to waste time learning to roll! He can get right into the techniques. And since he's not spending half of his class time taking ukemi, he should be learning the nage role twice as quickly. And of course, he is getting plenty of personal instruction from his teacher. So why couldn't he learn Aikido this way?