In a difficult start to his second season in Formula E, Cassidy showed flashes of pace and took two fastest laps in the opening four races, but difficulties with strategy and getting caught out in fights severely dented his points haul.
Cassidy was vocal on the radio during the Mexican race, having expressed his dissatisfaction with the attack mode strategy, while a chance to score points in Rome's second race went begging after a clash with Sam Bird.
Envision also struggled in the races at Berlin, Jakarta and Marrakesh, which left Cassidy on just 16 points with six races to spare.
But a turnaround in form at New York meant that Cassidy scorched to pole in both races, winning the red-flag shortened first race despite crashing out amid a heavy downpour. He was thus sent to the back of the grid in the second owing to the required battery changes overnight.
Cassidy also grabbed third in the first London race, and collected more points in both Seoul races to get within three points of the top 10 in the championship.
The Kiwi explained that changes in the team, particularly on his side of the garage, had taken a while to get acquainted with - particularly given the compressed nature of a Formula E weekend.
"There's no secret we've had a lot of changes," Cassidy told Autosport.
"They weren't really just at the start of the year, it was more round three onwards. And I think I've mentioned before, I've always worked with very strong people, the guys in our team before, very smart individuals. The guys who are here now are extremely smart individuals as well.
"Formula E is not an easy championship to walk into on a race weekend, because the cars and the series are so different that it takes time, not just to really learn each other but also the procedures, the car, the systems.
"And now we're improving that every weekend. You look up and down the pitlane and a lot of these teams have been together for a long time.
"So to have change is never easy, but it's not a negative and I'm super happy with everyone I'm working with. It just sometimes takes time."
Speaking about his New York win, Cassidy said that it had been a long time coming. But, more than anything, he was pleased to have enjoyed a clean weekend following the earlier difficulties across the season.
The Kiwi added that he felt he was always able to show strong pace in Formula E machinery, but that he wasn't always able to exploit it.
"It's more what I feel was a long time coming: having a clean weekend or clean day in FE. I feel like I've been quite strong on speed ever since I joined the championship.
"And I've had days, especially last year, that have 90% come together. This year, I feel more experienced, more complete, but I hadn't had those clean weekends.
"So it's just nice to have nothing kind of go wrong, me putting it together as well. And that combination worked out."