In the midst of Red Bull's struggles with its RB20 Formula 1 car last year, the team suspected that correlation problems with its old Bedford windtunnel were a big factor.
The lack of consistency between the track, CFD data and the windtunnel triggered an interesting comment from Christian Horner at the time.
"When they don't add up, it's like having three watches that are all telling different times," he said. "Which one do you believe? Ultimately, you believe the stopwatch on the track because that one doesn't lie."
While Red Bull slowly uncovered the weaknesses of its 2024 challenger after the Italian Grand Prix, it also doubled down on getting the third of those watches - the windtunnel - to synchronise a bit better too.
Getting the right answers was not a matter of Red Bull needing to commit to a refurbishment, or the technology inside needing to be being brought up to date.
Instead, the key to Red Bull making progress was in better understanding the impact of some particular quirks with its facility.
Red Bull has known for a while - and it is something that will be cured by the new state-of-the-art windtunnel that is under construction at its Milton Keynes factory - that its Bedford building is particularly susceptible to the British weather.
The tunnel at Thurleigh Airfield was built as part of the Royal Aeronautical Establishment's complex near Bedford in 1947.
The specific windtunnel that Red Bull now has was originally used for testing aircraft characteristics during take-off and landing, as it featured a rolling road that would simulate runways.
When Jaguar bought the tunnel from Arrows in 2004 prior to Red Bull's buyout, it was repurposed for motor racing use, and has been regularly updated since.
But while the technology on the inside was kept as up-to-date as possible, Red Bull could not escape the legacy of the old concrete outer buildings not being as well insulated as a state-of the-art modern facility.
This means that it is exposed to air temperature fluctuations - so tests are never taking place in conditions that are consistent.
And, in the world of F1 where tiny details matter, trying to understand the air temperature implications - especially during a 2024 season where the margins were so small - has proved to be a real challenge.
"We've always known the limitations of the tunnel," Horner explained last year. "But I think as we've really started to push the aerodynamics of these cars now, and you're into really fine-margins, then those limitations show themselves up."
He added: "We've got a facility that is a 60-year-old windtunnel. It is a relic of the Cold War.
"It's been good enough to produce some fantastic cars for us over the years, but anything under 5°C, we can't run it. Anything over 25°C, it becomes pretty unstable."
Red Bull technical director Pierre Wache explained that when the team is working around such fluctuations of temperature, it is hard to be completely sure about what the data says - because how air molecules react at one temperature is not how they behave when things are a couple of degrees warmer.
The same test on the same car in the same windtunnel on a cooler day can produce very different results.
"The main problem is accuracy and repeatability," Wache told The Race. "When you develop a new concept, this tunnel could work very well.
"It's more when you are fighting the flattening development curve, it's difficult to work with it because we are very dependent on the temperature in the UK.
"There are big swings between cold and hot. It's very difficult for us.
"We've tried to improve it inside, and have developed it a lot over the years, but some physical aspects you cannot change.
"For sure it affected our rate of development compared to other teams, but I don't want to find excuses."
Red Bull has long known about the weakness of its Bedford facility, and has toyed for years with the idea of building something new.
However, as Horner explained, things got delayed by regulatory uncertainty.
"The shareholders signed off two years ago [on a new windtunnel]," he said. "You see the big crane on site, there is a new tunnel being built.
"Now, there was a point in time that windtunnels could have been banned. And there was a discussion about whether that was going to be the case, and whether CFD would overtake or not. Adrian [Newey] held off pushing for a new tunnel until there was clarity on that.
"But it got to a point where Aston Martin wanted a new tunnel and the FIA changed their stance.
"So it was a question of: 'Look, we have to do this because the regulations dictate that, within a cost cap, the tunnel that we're running is grossly inefficient'."
Work is advancing on the new windtunnel at Milton Keynes, which should be finished next year in time to help with work on Red Bull's 2027 car.
Until then, as Red Bull's sister team knows, it will be a case of working around the deficiencies with the current facility.
Jody Egginton, technical director of the sister Racing Bulls squad that also operated in the tunnel, explained: "It's a harder tool to work with on a very cool day or a very hot day. You must keep your wits about you to ensure you've not inadvertently lost control of the baseline.
"We're aware of it. But it's like an old house. You just have to keep an eye on it."
