Dropping by to add another use case that’s hurt by this:
Having forgotten this bug, I just dropped by talk.jekyllrb.com and searched “3.0 eta”, looking for a topic I knew already existed. This search garnered no results of course, while “eta” got me exactly what I wanted.
The fact that you actually lose search results by including an invalid search term can be pretty detrimental on technical forums where searching for specific versions is not uncommon.