So... I thought that when booking AGR for long distance, that you had to take the shortest number of segments (if available), and only if that route wasn't available could you extend the route.

So if CHI-SEA was available on the Empire Builder, you couldn't opt to take CHI-??? on the California Zephyr, and then run the coast on the Starlight.

Likewise, you couldn't take CHI-POR on Empire Builder and finish the trip POR-SEA.

If something has changed, that's great.

If not, I fear that though you CAN book it on AGR, you'll be charged extra points for the extra 'one zone segment'.