If your point was to say that after 36-48 months we will start the ascension to Alpha Centauri, then we certainly agree, and the most sensible timing for purchase is NOW. 
My logistic analysis is akin to your own log regression analysis. It does not say much about the bubble fluctuations that we have seen in the past and expect in the future. Rather it suggests some average trends.
And could not agree more with your timing advice.