Vandoorne claimed his first pole for DS Penske after beating Antonio Felix da Costa in the qualifying duels, and led the early stages of the race before fading back to sixth at the finish.
The unique nature of the Brazilian circuit, which included long straights not commonly used in Formula E, meant drivers were reluctant to lead in order to save energy in the slipstream.
Despite attempts to let competitors move ahead, the chasing pack generally remained behind Vandoorne for the opening third of the race, costing him energy.
The Belgian, who went on to finish sixth as Mitch Evans claimed victory for Jaguar, believes his efforts at slowing down to let others ahead had started to verge on being dangerous, such was the disadvantage of leading.
“I was trying to let them past, I was lifting crazy early everywhere,” he said.
“That’s why you saw on the TV sometimes some kind of weird double overtake. It’s just because everyone was lifting so early.
“I can’t stop the car on track at some point, it’s still a race. It’s just the penalty of being at the front and pumping a hole in the air.
“There were some instances where it was quite dangerous in Turn 1, because I was lifting so early and Antonio kind of went alongside, Mitch went alongside.
“I think at one point we were almost four-wide into Turn 1 because everyone is trying to not lead the race. It became a bit dangerous at some points, yes.”
Having started alongside Vandoorne on the front row and shadowed him in the early stages, da Costa dropped down the order after an error at Turn 1 and finished fourth at the flag.
The Porsche driver believes that the extensive use of coasting probably went too far, with the new Gen3 cars already more suited for slipstreaming than its predecessor.
“I thought Stoffel did a great race with how many laps he led and for that he was a windbreaker for all of us,” he said.
“I’m not sure if I like it.
“I think it’s cool, but this car really provokes it anyway and this just makes it too much, so I think to a degree what we have in the other weekends and races is fine, but here is a bit too much.”
