I guess, the short answer to your last question:
"Basically, I guess I'm asking if there's any way to get the truncation
operator to actually function inside a quoted expression?"
is: no.
FULLTEXT indexes are built on complete words (minus the stopwords), not parts of words. The syntax which behaves the way you are expecting is the LIKE and REGEXP expressions, not MATCH/AGAINST.
The only way I can think of to help you out would be to standardize the data before putting into this column. You can run it through an expression to clean up the street address and standardize it, optionally breaking the single field into three or four fields, like StreetNo, StreetName, etc. This will get the address data into the most efficient format for indexing by non-FULLTEXT indexes. FULLTEXT indexes really weren't meant for this type of scenario...
Jay Pipes
Community Relations Manager, North America, MySQL Inc.
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