One area where the coaching change has had a significant impact on the team is at practice. One would expect practices to be the most significant change a new coach would bring, but Roy switched things up with an unusual new rule. He made it so that all players must come off the ice at the same time.
All of that being said, the team's performances have not significantly improved under Roy. Following their most recent loss to the Florida Panthers, the team is now just 1-2-1 under Roy, with their single victory coming in his first game with the team.
Even in the game where they won, the Islanders had to rely on their goaltender as they were heavily outplayed by the Dallas Stars. They were lucky to squeak out the overtime win. So it seems that the team simply may not be good enough to compete for a playoff spot this season.