Dog and pony show was a colloquial term used in the United States in the late 19th and early 20th centuries to refer to small traveling circuses that toured through small towns and rural areas. The name derives from the typical use of performing dogs and ponies as the main attractions of the events.
Performances were typically held in open-air arenas, such as race tracks or municipal parks, and in localities that were too small or remote to attract bigtop performances. In the latter part of the 20th century, the original meaning of the term has largely been lost.
The term has come to mean any type of presentation or display that is:
1 somewhat pathetically contrived or overly intricate or
2 put on for purposes of gaining approval for a program, policy, etc.
http://en.wikipedia.org/wiki/Dog_and_pony_show