What you posted is not a script, but a calculation.
It will return "RETL" for USF Reddaway, but returns null for "Bob Reddaway trucking".
This looks like data that might be better handled with a look up table of carrier names and associated acronyms. Then, adding/removing/modifying data becomes a data entry task on that table (no FMP developer needed) instead of a design change to the calculation (developer needed).
Thats a great point.