On Dec 4, 2:27*pm, Pat Flannery wrote:
....as was suspected in recent weeks:http://news.bbc.co.uk/2/hi/science/nature/7765818.stm
This will further drive up the costs of the already way-over-budget program.

Pat

Another way to look at it is to not waste the money and work invested
in it already, and to take it slow to make sure that the thing will
work as advertised. They only have one spacecraft and it must not
fail.
Plus it keeps the spacecraft engineers at JPL employed.