Originally Posted by speed
I can't remember a time where a Canadian Prime Minister was overridden in his choice to pick a GG, so as far as all practicality is concerned, they are chosen by the Prime Minister.
That may be true, but they do not work for the PM, they do not do the PM's bidding, and they work until they retire (or do something unpopular and are asked to retire by the Queen at the bequest of the Canadian people as represented by the PM).
When the GG position is next up for grabs, the Queen could rightly appoint Prince William or Harry (maybe not yet, maybe once they are older) as the GG. It has been talked about for Australia (Charles was almost GG for awhile), and is not beyond the Canadian constitution either.