I do not like data that indicates what I want, because that's not useful. Again, that's what you're doing and you've moved goal posts a few times now and have ignored a huge portion of what I said (and what you said originally).
Either the fancy stats are the best at predicting winners and losers, and do so regularly, or they're just another stat like everything else. What is the success rate? How are you measuring predictability?
You know what's crazy about that? Half the league is above 50%. So strange that the teams that make the playoffs would be above 50% xGF. Let's take a look at the teams last year and see how they did:
1) Boston lead the league in xGF% during the regular season. It's odd that they were just a Wild Card team and were bounced in the first round by Carolina (who is #5 in xGF%).
2) Florida was number two. They won the President's Trophy, so that's cool. They beat the Capitals (#15), the second Wild Card team and then were swept by Tampa Bay (#9). That's kind of weird, no?
3) Toronto sat at number three. How'd that go for them again? They also lost to Tampa Bay (#9), but in the first round.
4) Calgary was number four. They had a nice run to the second round. They beat Dallas (#14) in the first round but lost to Edmonton (#12) in round two, in five games.
5) Carolina was five. They beat that top team in the first round like I mentioned earlier. Then they lost to the Rags (#24).
6) Minnesota will buck the trend for sure here. Nope, they lost to St. Louis (#23) in the opening round.
7) We're not doing so well, but maybe Los Angeles will change things up a bit. Checking my notes it looks like they lost in the first round too...against Edmonton (#12). Huh, that's odd.
8) Pittsburgh, here we go. They're the real deal. They beat the Rags...oh no, wait, they lost in the opening round to the Rags (#24).
9) This is it. Tampa Bay to the rescue. They beat Toronto (#3), then beat Florida (#2), then they win once more against the Rags (#24). Unfortunately, they lose to Colorado (#11) in the finals.
10) Vegas must've been pretty good for these stats. They won...nothing, they didn't even make the playoffs.
I'll stop there. Of the thirteen match ups mentioned above if you were to expect teams with the better xGF% to win the series you would be really sad. They were 3-10.
Now let me do xGA since you say it's the best.
1) Boston. Still a first round exit.
2) Minnesota. Still a first round exit.
3) Nashville. First round exit.
4) Calgary, second round exit to Edmonton (#15).
5) Tampa Bay, cup final loss to Colorado (#8).
6) Seattle. Didn't qualify.
7) Toronto. First round exit to Tampa Bay (#5).
8) Colorado. Cup winners.
9) Pittsburgh. Still a first round exit.
10) Washington, still a first round exit.
So of the top 10 teams in xGA, six of them didn't win a round (and Seattle didn't even qualify).
If that's the level of predictability we're talking about with fancy stats, they can f*** right off.
I mean, you can just look at goal differential and say that teams who have a higher differential are usually better. So insightful. Every team that made the playoffs last year had a positive goal differential, except one. Thirteen of the top 16 teams in goal differential made the playoffs, amazing coincidence. Did you know that teams that give up fewer goals than other teams are also more likely to make the playoffs than their counterpart? Who would've guessed?! Oddly enough, teams that score more than the rest of the league also make the playoffs more frequently than those that don't. What do you think about that? This next one is pretty crazy, teams that win more are more likely to do better in the standings than teams that win less. f***ing nutty.
If all you're doing is predicting who will make the playoffs with the fancy stats, what's the point? There are enough stats that do it just as well, and are way less complicated.
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As for your obsession with me wanting Lamoriello and the Islanders painted in a positive light, I'm not sure where you get that from. I mentioned at the beginning of last year and this year that they're a bubble playoff team. That is sure some rose colored glasses I'm looking through. It's so strange that they finished in the 9th spot in the Eastern Conference last year. Also strange that I made that prediction before any of the fancy stats for the season existed. Where are they right now? Oh, in that same position. Wild how I was able to guess that.
Just because I disagree with your assessment of trades, because you want to view Lamoriello negatively to push your narrative, doesn't mean I want him to look good. I'm as objective as I can be with the organization, with the exception of Bailey, and I call'em how I see'em. Crying about overpaying for Pageau or the first to acquire Romanov is some of the most nonsensical shit that really uneducated fans complain about. We've seen so many first round busts over the past ten years and still people believe that they'll win that lottery. I'd go back and do either trade again in a nano-second. Pageau helped the team get to back to back Eastern Conference Finals, and is a solid third line center you never have to worry about. Romanov, I'd even add to that trade after seeing him play. Mobile, physical, shot blocking young defensemen don't grow on trees and he's so far ahead of the learning curve for defensemen already.
If you don't like the trades, fine, but the five dollar scratcher draft picks trying to win a million dollars rarely works.
You want some issues I have with Lamoriello? I didn't like Trotz being let go. I still think there's more to it than the need for a new voice, but it doesn't really matter. I prefer defense first teams and this team doesn't do that anymore. I wasn't happy with Chara being a regular last year. I'm not happy with Aho being a regular this year. I wanted him to make a move for a forward in the summer. I'm not thrilled with the fourth line all getting new contracts and would've dismantled that line a few seasons ago. What you perceive as liking or viewing things positively is simply the fact that I understand some of the decisions he's made, even if I disagree with it. He's old as dirt, he's not going to be doing a rebuild, even if I think he should. I understand that, it doesn't mean it's something I'm thrilled about. There's a spectrum of good and bad, it isn't columns of good and bad for me when judging a GM.