Mercedes has spent the opening six rounds of 2026 making the new era look worryingly familiar: six pole positions, six wins, and a points cushion that’s already forcing rivals to talk in damage-limitation terms rather than championship intent. So when the FIA’s first pass at ADUO has effectively handed Mercedes an internal combustion engine upgrade opportunity, it’s landed in the paddock with a thud rather than a shrug.
Sky Sports F1’s David Croft has been among those openly struggling to square the circle. In simple terms, ADUO — Additional Development Upgrade Opportunities — is the mechanism designed to stop any one power unit supplier drifting too far off the pace early in the regulation cycle. The twist this time is what the FIA’s benchmarking has reportedly identified.
Sources indicate Red Bull Powertrains’ DM01 has been deemed the reference internal combustion engine on the grid. That’s a headline in itself: Red Bull’s first in-house ICE, and it’s already the benchmark. But the knock-on effect is the part that’s inflamed debate. Because ADUO only measures the ICE element rather than the complete power unit, Red Bull’s “best” classification in that specific area means it can’t take an ICE upgrade under the scheme — while Mercedes, reportedly at least two per cent down to that benchmark, can.
On paper, that’s the system working exactly as designed. In the competitive reality of 2026 so far, it looks like the front-runner being offered another lever to pull.
Croft’s confusion is rooted in optics as much as engineering nuance. Mercedes leads Red Bull by 72 points, sitting on 244 after six race weekends, and has looked the class of the field across qualifying and race trim. The outside impression — and it’s the one that matters when you’re selling a sport — is that the best overall package is now being allowed to improve further in one area, while a rival that’s already behind on results is blocked from touching the component it’s apparently strongest in.
“Once again it seems we have found a way to help people catch up, but then at the same time found a way to kick ourselves in the backside with our own feet in F1 terminology,” Croft said on The F1 Show podcast. His broader point is familiar: Formula 1 has historically resisted anything that smells like balance of performance, and even if ADUO isn’t BoP in the purest sense, it’s hard to argue it doesn’t carry a similar philosophical aftertaste.
The finer detail matters. ADUO doesn’t cover reliability, and it doesn’t judge “the engine” in the way fans and even some team narratives tend to frame it. It is explicitly tied to the internal combustion engine. That distinction is precisely why the current outcome is so awkward: Mercedes can be behind on ICE performance as defined by the FIA’s metrics, yet still be crushing the field thanks to strength elsewhere — whether that’s other aspects of the power unit package or the car wrapped around it.
And that’s where this first ADUO cycle has exposed the potential flaw. If the stated aim is competitive convergence, then a component-by-component benchmark risks treating the symptom instead of the illness — or worse, treating the wrong patient. A team can be “behind” in a narrow subcategory and still be the sport’s pacesetter; another can be “best” in that same subcategory and still be losing races by enough that the distinction feels academic.
Croft’s proposed fix is blunt: loosen the restrictions, at least early in the cycle. Rather than selectively granting upgrade windows under ADUO, he’d prefer the FIA simply lift the cost cap constraints on power unit manufacturers and allow them to spend their way towards a robust, optimised product.
“What I would prefer to have seen in the first – and maybe second – year of these current power units, to enable all the engine manufacturers to make a power unit that is reliable and is the best that they possibly can, is not put them under the cost cap restrictions,” he argued. With new major players bedding in — Audi now part of the grid, Red Bull Powertrains still building credibility as a standalone operation, and Honda returning — the case for a cleaner runway is understandable, even if it runs against the sport’s cost-control instincts.
The counterargument is obvious: open the spending taps and you risk locking in advantage, not removing it. The whole point of a regulated upgrade framework is to prevent an arms race where the richest operation simply sprints away. But ADUO’s first big moment has still managed to create the one thing the FIA can’t afford right now: confusion about what the rules are trying to achieve.
There’s a bigger question bubbling underneath all this, and it won’t go away if Mercedes continues to sweep weekends. Should ADUO be tied to the power unit as a whole rather than a single element? If the objective is to avoid one supplier being stranded, it’s difficult to justify a tool that can declare a “best ICE” for a team that’s losing ground in the standings — and then conclude the championship leader is eligible for additional development in that same area.
For now, what’s clear is that ADUO has arrived with good intentions and messy optics. And in a season already tilting heavily towards one team, the last thing Formula 1 needs is a rule designed to close gaps becoming another reason fans feel they’re widening.
