Originally Posted by
D582
UK APD would not be different. UK passenger service charge would be different between a UK to Europe and UK to non-Europe departure. However, flying LHR-FRA-DXB would then attract some German taxes so not really sure there is are any savings.
So I would say the answer to your question of would AAA-BBB-CCC ever be cheaper than AAA-CCC… maybe?
LHR-DXB $453
LHR-FRA-DXB $446 (lower UK PSC > added German taxes)
LHR-ARN-DXB $408
LHR-VIE-DXB $390
The same logic also applies to using other BC airports as connections from YVR, which has a cheaper AIF for intra-provincial flights; for example, if you'd like to save $20 getting to YYC, you can connect in YLW rather than fly non-stop. Although the cow was asking about partner itineraries, so it wouldn't be applicable to the original question.
I'm sure we could find a few more weird cases like this where the taxes differ.
The one other thing I can think of, where the points cost is actually lower, is if you try to price something as two separate bounds, and moving to a shorter bound more than offsets the cost of the added bound. I'm pretty sure I had looked at a TPAC itinerary a few months back where it was cheaper if you booked the connection as a separate bound, because AAA-CCC was in one distance band, but AAA-BBB was in a lower band, and the extra cost of a new BBB-CCC bound was less than the difference in points cost between the two bands (AAA-CCC vs AAA-BBB). I can't for the life of me remember the route, and I just checked out a few things with GCmap and the reward chart, but it may have been something right around 11K on a North America - Pacific itinerary, where the pricing steps up 27.5K, but an intra-Pacific flight up to 1,000 miles is only 20K.
But I think this type of thing will be pretty rare, given the jumps in pricing from band to band. It may also require this to be a comparison of a two-stop itinerary to a one-stop (i.e. AAA-BBB-CCC-DDD might be cheaper than AAA-BBB-DDD). But I can't, for the life of me, remember what the routing was, and it's possible it was a two-stop being cheaper than a one-stop, rather than one-stop cheaper than direct.