the 5k OW / 10K RT numbers were examples to explain my process.

I suggest you talk to your corporate travel agent (we use AmEx) next time you're looking at a trip to see if there's a difference between one way tickets out and back versus round trip.
You'll be surprised at how many times it's the same price... I wouldn't book it this way if it was more expensive, and this is my 4th or 5th time booking this way this year...
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