No, you still need to use the meta query. This filter allows other plugins to change the default query behavior for short word queries. Short words are words less or equal two characters. Databases generally can not search for small words so they have to be dealt with specially. Connections defaults to search for words that end with the short word. Another user wanted to change this so it would search for results that contain the short word. This filter allows that user to write code to change it to work how they want.
Hope that explains it clearly!