I suppose it was naive of me to suppose that somebody had not already taken whyaduck.com. Apparently it was once a very popular Marx Brothers website. Now the site is dormant, but somebody's camping on the domain name and apparently wants $10,000 for it. Oh well ...
But all is not lost. It appears that the names "whyaduckweb," "whyaduckwebworks," and "thatswhyaduck" are not taken. Comments regarding preferences for these alternatives will be happily taken. Right now I'm personally leaning towards "thatswhyaduck."