From the launch of the MCL60, Stella stressed a need for the team to remain “realistic” as it started the campaign with an underbaked design.
In the meantime, he led an overhaul of the technical division by getting rid of director James Key before hiring David Sanchez from Ferrari and experienced Red Bull chief engineer Rob Marshall.
A major upgrade for the Azerbaijan Grand Prix represented how the car should have started the year and since then, the team has battled to keep pace with rivals in the development war.
With the calendar moving away from street tracks that dominated the start of the campaign to the conventional Barcelona circuit last weekend, Stella reckoned the more representative Spanish GP layout had offered information on why the MCL60 switches behaviour overnight.
This came after Lando Norris qualified third before sustaining first-lap damage to finish 17th. Meanwhile, rookie team-mate Oscar Piastri started ninth on the grid before falling to 13th.
Stella said of a straightforward race that passed without a safety car or rain: “I think the only thing that it really adds is [the information on] this almost opposite behaviour of what happens in qualifying compared to what happens in the race.
“We don't only have to look at the aerodynamic behaviour of the car, and we know that we have to take a step forward from an aerodynamic point of view.
“But clearly, we also need to get our tyres to work in a better range during the race.
Source: Autosport