Chicxulub and the K/T boundary

I can't find the remnants of the thread about dinosaur extinction,
but just happened across this relevant URL:

http://hoopermuseum.earthsci.carleton.ca/saleem/keller.htm

"Recently, Dr. Gerta Keller and her team at Princeton proved quite 
conclusively that the Chicxulub crater predates the Cretaceous-Tertiary 
boundary by about 300,000 [years]. She challenges the notion that the 
Chicxulub crater was impact that killed off life 65 Ma.

Dr. Keller believes the K/T extinction was caused by multiple impacts, 
volcanism and climatic changes. The Chicxulub impact, 300,000 years 
before the boundary, stressed the ecosystems on Earth causing species 
numbers to be reduced. Another impact at the K/T boundary (the one 
synonymous with the iridium anomaly) coupled with the volcanism in India 
further accentuated the loss of species. These events combined caused an 
enormous amount of change to the climate which adversely affected the 
biota at the end of the Cretaceous, effectively driving them to extinct 
in large numbers."

See also:
http://www.physorg.com/news80320081.html

http://gsa.confex.com/gsa/2006AM/finalprogram/abstract_113080.htm