Aston Martin has played down suggestions the team is now consistently going backwards despite constant efforts to add developments to the 2023 car.
To address a mid-season slump following Fernando Alonso's early string of podiums this season, another serious upgrade was added to the car in Austin - where Aston Martin had a woeful weekend.
"Aston seem to have made the car slower and slower with every upgrade," observed McLaren's Lando Norris. "For us it's been vice versa."
So woeful was Aston Martin's pre-Sunday performances at the US GP that both Alonso and Lance Stroll started the race from the pitlane - having breached parc ferme rules by completely overhauling the cars' setups.
Alonso told DAZN: "On Saturday we did the race with the new (upgraded) car and on Sunday Lance did it with the new one in a different configuration and I had the old one was a setup we know the best.
"Now we will put everything on the table and draw the conclusions," the Spaniard added.
The early analysis, however, is that Aston Martin already understands why the performance slumped so badly before the revised Sunday setups.
"It was a super race," said Alonso, who ultimately retired from the US GP with floor damage.
"There was suddenly a lot more pace in the car. We could overtake the midfield with some ease and we were even getting closer to (George) Russell. So I think it was good news.
"We wanted to leave Austin at least with some clear conclusion going into Mexico. The race was more of a FP0 (free practice 0) to get to FP1 in Mexico prepared."
Team boss Mike Krack agrees with Alonso that the back-to-back comparisons on Sunday gave the engineers enough feedback to know the latest upgrades were not a failure.
"Right now we only have the laptimes and the results so we still have to analyse, but we don't think the new update package is bad," he said.