Ice-Age Meteorite Strike?

I have read various bits about this supposed strike (California's Channel Islands hold evidence of Clovis-age comets- a hexagonal form of diamond suggests impact about the same time the pygmy mammoth went extinct), but from what I've seen, it's not widely accepted. Do any of my geology readers (and I know there's a few of you out there) know anything more about where this the acceptance of this impact stands stands? I seem to recall a hypothesized impact in Canada's NWT, that was later tossed out, at about the same time in the past.

The reason I ask is that I saw a presentation by Chris Goldfinger at the 2002 GSA Cordillieran Section Meeting here in Corvallis, where his raw data was composed of highly detailed bathymetric maps of the Channel Island Area. He pointed out, basically in passing, that there were two unnaturally circular features on the images, and that he wondered if they might be impacts... but that it seemed unlikely to have two youthful impacts right next to each other. I told him afterwards that impact pairings and multiples were not really all that rare. A close pass to a planet can tidally disrupt an impactor (leading to two or more close by impacts in both time and space), and paired asteroids have turned out to be not uncommon.

Interesting...