Can someone tell me why this routing [IAH-SLC-RNO (dest)-SLC(stop)-DFW] is valid (i.e prices at 25k) but this one [IAH-SLC-RNO (dest)-SLC(stop)-MEM-ATL-RDU] is not (i.e. prices at 50k)? Is it a MPM issue? I feel like those are structurally equivalent in that they are round trip itineraries with an stop over on the return. Of course I am using the online tool but I don't want to call Delta unless I know I am right... Ive searched for each segment and they all have low level availability.