having the luxury of scrutinizing the method and retesting: to "normalize" domains and skip the www skewed results - not all websites do their redirects across

having the luxury of scrutinizing the method and retesting: to "normalize" domains and skip the www skewed results - not all websites do their redirects across apex to www (and schemas). Some servers weren't answering the request with the default curl accept header / and needed encouragement. I retested the 000 class of .de ccTLD (1227) and found more than a third (473) of them answering when prefixed with www. Lots of german universities were false negatives - if this is representative I cannot tell, just a hint to retest.