I've recently been musing over the idea that the aeons are not time spans, rather that they represent a paradigm (A set of assumptions, concepts, values, and practices constituting a view of reality).
So as we know the aeons have different characteristics, formula etc. these would be the base assumptions, concepts, values of the current/dominant paradigm. Many different religions and systems can be built from the same paradigm. We also know that the values in a culture shift and change with the times while still staying within that paradigm. The new aeon represents a general shift in the values, beliefs that has finally broken outside the old paradigm and must now be defined in a new way.
My point is that Crowley, in establishing Thelema did not create the new aeon, the aeon(paradigm) has come about in the general consciousness of our culture. That is why there are so many people who know nothing of Thelema that one might label a 'Thelemite'. Crowley then is just the first to point out the shift, as the trend was just occuring, and Thelema is only one possible "religious" structure that can exist within this aeon/paradigm.
So when trying to promote the law, we should consider if it is better to encourage a pure Thelemite approach, or perhaps just get people to wake up to the new aeon? Many people follow the new ways without even realizing it already. Since Thelema seems to be the only structure built on the new aeon, it would follow that anyone who becomes aware of the new aeon would naturally be drawn to it eventually.
Anyways, I hope that all made sense, I'd love to hear your thoughts on this.