There's hold luggage (whats checked in) and hand luggage (whats carried aboard). The reason most people carry so much luggage onto the aircraft is to avoid paying a surcharge if they are over weight on their checked in baggage. I fly BA a lot and they are generally brilliant, even if you are slightly over they will generally not charge you, as for your carry on luggage I have seen people getting on flights with 3 or 4 decent size bags when they should only have one plus your Duty Frees. This is in contrast to Ryan Air and EasyJet who charged me £40 cash, no credit cards accepted, for taking a plastic carrier bag onto the Gatwick flight and they confiscated it off me and put it in the hold! The only fly in the ointment is if you have to get a flight other than BA to get your connecting flight to Vancouver, if your BA all the way it's no bother as your bags will be checked straight thru to your final destination. As you may have gathered I hate low cost carriers because for one thing they aint low cost.