Well, I can report that a one letter/number search can provide great results using the new beta search.

I searched NW WP Forum for 2% (as it turns out it only searches for the 2 in this case) and found three threads on the "2% club" without even adding club to the search terms. Results were posted in 2% - can I get a straight answer ? in answer to a user who said it wasn't possible to search for 2%.