This feels a lot like "Of course they use their hands, they couldn't give you a massage otherwise" but it's in reply to a news article about the person who agreed to being touched being punched.

When I hit search, do the search right then. Don't grep out of a stored cache of prior searches.

The thing that makes it possible for search to be fast is pre-crawling and pre-indexing.

Some other engines don't do this, and the difference is remarkabe. Try a full-content search in Windows 7, you'll be staring at the dialog for two minutes while it tries to find a file that's in the same directory as you started the search in.

You said nothing about fast in your original though, so now you've moved the goal posts

I'm not really engaging in forensics-style debate. If you don't already know why "fast" is so integral to search as a feature that it goes without mention, I don't think we are enough on the same page to discourse on the topic.

I think returning results in a timely manner is more than an acceptable assumption.

The poster clearly thought about search in terms of the existing Google search functionality which is near instantaneous.

Usability matters to the average end user and a delayed search is not usable for most people.