The Briton, who started out as an engineer at McLaren Automotive 21 years ago, led Mercedes-EQ to electric title doubles in 2020-21 and 2021-22 with Nyck de Vries (27) and Stoffel Vandoorne (30) respectively.
Formula One giants McLaren, also racing in electric Extreme E and IndyCar series, took over the team from Mercedes and James stayed on as principal in a back to the future move.
"I was always very proud of the fact that at Mercedes we were the only brand with a foot in both camps, Formula One and Formula E," the team principal and MD of Saudi-backed NEOM McLaren Electric Racing, told Reuters.
"And now that we've transitioned to McLaren we're still the only team with a foot in both camps."
Past form counts for only so much, however.
The team - like the city-based series itself with faster, smaller and lighter cars - has hit a reset button and McLaren will be using a powertrain provided by Formula E regulars Nissan.
There are also new drivers in triple German touring car champion and former Audi racer Rene Rast (36) alongside British rookie Jake Hughes (28), promoted from a previous role as Mercedes reserve.
The team are based at the Bicester Heritage centre in central England rather than McLaren's Woking headquarters near London, although the simulator will come on line down south later in the year.
"Up until now as Mercedes we were a manufacturer and competitor whereas now we are a customer team of Nissan so that brings a different dynamic," said James.
"What we’ve tried to do is make sure that with what we are able to carry over and continue, we keep as much stability in the system as possible.
"So the vast majority of the team is the same team that won those two world championships before - the engineers, the mechanics, the admin staff, the commercial team by and large are the same.
"We’re going to very much have key parts of the overall operation based in the McLaren Technology Centre as well. That way we end up with the best of both worlds."
Asked about continuing the run of titles, James said the focus was on doing the best possible with a particularly complex new car and technical teething problems to overcome as well as rivals taking a step forward.
"There's still a huge amount of work, both for the series as a whole but also for us as a team, to make sure that we can realise our full potential. So we won’t be resting on any laurels quite yet," he said.
"It’s almost impossible to say where you stand against the competition, we’re really not going to know that until we get out to Mexico and start racing in earnest.
"Time will tell as to whether we then put ourselves in a position to win races and ultimately championships.
"But be under no illusions, as McLaren that’s very much our aspiration and the goal we will be working towards."
