Shareholder, I don't think that's true, since it's a US-US ticket and AC can't fly people within the US (or did you mean use AC points to claim UA flights?).

I asked about IAD-somewhereUS last year and they told me it would cost 2x15K to fly AC via YYZ, or 1x25K if United flew between the two points. I didn't pursue it though.

andrew