Reader Question: Should I transfer Southwest Points to AirTran Credits?

Joanne writes:

"I have accumulated approximately 55,000 Southwest Rapid Rewards. I see that I have a Southwest flight credit that is expiring, and Southwest wants me to use 18,000 points to create a reward flight. I have my eye on a roundtrip award to Phoenix that costs 29,000 points. Is it worth it to do this? I am so confused. Any help is appreciated."

I can sympathize with Joanne's confusion.