Originally Posted by
Often1
Before going through all kinds of skullduggery, why not price the change? On a fairly typical ticket, the cost will be $300 +/- fare difference. If the fare difference is negative, that will eat into the $300. For all you know, it may cost you just about the same to fly to make the change.
But, if it doesn't and LAX-IAD is your final segment, it won't much matter if you noshow, although this is not something you should do repeatedly.
One thing which will not work is purchasing LAX-DFW on UA. UA's systems will see the "impossible" tickets. If you are lucky, you will get a call. If you are unlucky, one or both will be cancelled. So, if you do this, fly somebody else.
+1. Bear in mind that even if the new ticket is less, you'll need to pay the $300 change fee with fresh money and receive difference in flight credit. Or tell you you wanted to go to Dallas, but ended up in Dulles instead.