I'm eating a lot of crow because of how it turned out, but I'll always maintain that at the time of the trade it WAS a bad move. Though, since it happened, Subban had a couple good years and a really good playoff run, but now has regressed massively. Weber was good for a couple seasons, but since the last two seasons has reached another gear.
At the time, there was no arguments based on on-ice factors that could possibly justify this trade as anything more than a lateral move. Things have now changed... But please dont sell this as a shrewd move by MB, especially since the deal was short-sighted. Let's remember that shortly after, he went after Drouin and Alzner, stating that he had constructed "the best defence" since he began his tenure. Then, not long after, we were heading for a retool towards youth... Yikes. The trade is okay, fine even, but in the large scheme of things, was quite dumb. We now know we shouldve traded Subban for futures and prospects.
So MB was a visionary that accurately predicted Subban's decline, but couldn't see that the defence he built was atrocious ? He couldnt foresee finishing at the bottom of the standings, which led the team to acknowledge the need to add talent through the draft ? Nah... He was in "win-now" mode and it blew up in his face.