Boomers are those who were influenced by the extremely optimistic years from the turning point of WW2 until the first cracks in the dam at the outset of the 1960s. Xers are those influenced by the more pessimistic vibe from 1960 until Reagan stepped up to the plate. Influence determines generational characteristics. There is no Generation Jones, the real issue is the Boomer definition is too expansive and the Xer one is not expansive enough.
The data I’ve seen makes a convincing case that there is definitely a distinct generation between the Boomers and GenXers. The fact that Generation Jones has become so accepted nationally so quickly speaks to the existence of this “lost” generation.
Here’s a 5 minute video with over 20 top political figures discussing the existence and importance of GenJones: http://www.youtube.com/watch?v=1Ta_Du5K0jk