I've been trying to read entrails, and maybe I'm putting too much weight on an off-the-cuff remark, but Marc Bergevin now says that it's possible he might trade down, if I interpret his "We could have six (picks), we could have four or we could have eight" quote correctly.
Last week, Trevor Timmins threw cold water on the trade-down for more picks scenario, bringing up the 50-contract rule as one consideration. Obviously, it's better to have one solid prospect than two borderline ones when you're up against that limit.
The only way I see trading down from #25 as likely is if all the players the Canadiens would like in that range are gone when their turn comes, and their next tier is of players they feel they could mostly pick up later. They'd trade down to amass more picks, and then be in a position to 'reach' for Jonathan Ismaël Diaby in the second round, and possibly snag Jordan Subban with a later pick. This is semi-analysis, semi-daydreaming.
I think Mr. Diaby, as rough a project as he is, is the sort of one-of-a-kind player that other teams will have difficulty matching. Even if he never develops as a reliable defenceman, he'll still have value as a huge enforcer type who can be put in a lineup based on situations. He's already 6'6" and 240 lbs at 18, with a mean streak.
You don't wait and hope that guy falls down to you, you have to go and get him. The Canadiens' comparative lack of size in the system would make him extra valuable to us.