It's tempting to assume that adding talent makes a team better and subtracting it makes it worse, but it doesn't always work that way. Nashville was a seller at the deadline, but surged afterward and almost made the playoffs. LA didn't have Doughty and Arvidsson for last year's playoffs, but the team stepped up and, in particular, depth players like Durzi and Grundstrom played better than they actually were. This year, Doughty and Arvidsson are healthy, so the team hasn't had to step up to replace them and Durzi and Grundstrom have been mostly terrible. Similarly, they've gotten Fiala and Vilardi back and the team has played worse, as you noted. You can't just assume that a team will be better by getting players back. Talent is only half of the equation. Look no further than the most recent expansion team being tied 2-2 in a series with the most recent Cup champs. LA has a lot more talent than Seattle, but Seattle is holding its own against an equally tough opponent because of a strong team game (including a PK percentage double that of LA's).