Is 'Canadian' a racist slur?

From http://www.cbc.ca/news/viewpoint/vp_burman/2008/01/is_canadian_a_racist_slur.html:

What does the word "Canadian" conjure up in your mind?

Polite? Peacekeeping? Harmless? Heroic? A weak-kneed, pot-smoking, sexually-permissive anti-American? Or, perhaps, cheap?

This is a question being debated this week with both intensity and some humour in a variety of internet blogs in the United States.

The trigger point occurred over the weekend on the popular American website The Huffington Post, quoting a brief Canadian newspaper story that revealed that the term "Canadian" is being used in parts of the U.S. as a euphemism — as code — for a racist characterization of black people.

The comments wander off into how much one should tip in a restaurant, but I guess that was inevitable given the last two sentences:

The most startling revelation for me is that many Americans apparently tip 20% when they go into a restaurant.

That’s quite odd.

Perhaps one is supposed to tip less in Canada.