Here’s an insightful and realistic perspective on the real reasons for “5%” growth:
http://www.zerohedge.com/news/2014-12-23/here-reason-surge-q3-gdp
In short, two-thirds of the “boost” to final Q3 personal consumption came from, drumroll, the same Obamacare which initially was supposed to boost Q1 GDP until the “polar vortex” crashed the number so badly, the BEA decided to pull it completely and leave this “growth dry powder” for another quarter. That quarter was Q3.