Could it be that + is used by people who just don't know that Google treats it specially? Syntax of Google search is rather not common knowledge among general population. This might be a case especially when searching for books, songs, movies, magazines, etc. with '+' in title.
Example queries (random ideas):
- 18+ movies
- children + fire proverb
- 2+3D magazine
- C++
- ++ operator
Personally I often just copy-paste general things I'm looking for (like song titles) from websites or IM conversations, with whatever characters they happen to be containing.
EDIT:
There are plenty of queries with + signs in autocompletion hints in Google search - like 18+ clubs, 2+2 forums, 0+ blood type, NaOH+H2SO4, etc.
At a complete guess, i'd guess that their parser would check for usage of a plus that doesn't fit the boolean mould and doesn't count it as such. And i guess too, because like you say...autocomplete knows about it, it has exceptions for acceptable +'s that also aren't included in the malformed searches that the Google guy is talking about.
So i still can't really imagine how there are so many misused ones...
Example queries (random ideas):
Personally I often just copy-paste general things I'm looking for (like song titles) from websites or IM conversations, with whatever characters they happen to be containing.EDIT:
There are plenty of queries with + signs in autocompletion hints in Google search - like 18+ clubs, 2+2 forums, 0+ blood type, NaOH+H2SO4, etc.