Aeroplan and AC are their own worst enemy
I tried to book a slightly complicated Canada /multi USA city flight online with AC for myself and one on Aeroplan for the wife but got the usual invalid itinerary.
For the wife's I ended up using Aeroplan for 1st leg, and paid for the rest on UA
Due to this I booked all of paid flights on UA and get the status miles on AC amazing how bad their online tools are, oh well their loss.
My flights hit $1.8K, hers < $ 600 all the money going to UA
It's 2012, I should not have to phone AC to book multi-city trips, so I won't