Tell me, how it is possible? Are you talking about static or dynamic practice?
With one another? It's still comparatively static, because it's much hard to teach someone how to fit, unbalance and throw than how to fall. In fact, I would rather teach someone how to throw with an experienced uke than with a newbie of equal skill level as uke.
But as far as receiving technique is concerned, once the basic parameters of the fall have been inculcated in a newbie, it's quite possible to hand the newbie to someone with more experience for more dynamic practice, and as long as the more experienced partner isn't trying to ramp up the speed or power level too rapidly, the development curve is quite rapid. To tell you the truth, it was initially quite a shock to see how fast that curve could rise -- as long as the primary consideration is whether or not the student can fall safely.
If the question is one of elegance (and I'm not immune to the charm of beautiful ukemi), the time it takes to develop that is still considerable. I wouldn't claim otherwise for a moment. But to paraphrase Ellis' remarks above, this method provides a safe baseline from which someone can make a choice to work toward other kinds of ukemi in a safer fashion than the traditional model allows.
At least, that's my experience.