The largely unsung relationship between a race driver and their engineer is one of the most crucial in dictating success or failure in Formula One.
The increasing use of F1's in-race radio during race broadcasts has offered fans a glimpse into how it works. Whether it's Lewis Hamilton and Peter Bonnington's "Hammer Time", or one of Kimi Raikkonen's many icy responses to Dave Greenwood or whichever other unfortunate soul has been on the opposite end of his radio channel, it can be easy to narrow the job down to the small confines of these scattered messages.
But the relationship goes deeper than simply a line of communications during a race. Every shred of feedback between these two vital parts of a race operation will help dictate how quickly a team understands a new upgrade, solves a problem with set-up, hones in on ideal race strategy and so on.
One of the most frequently heard radio channels last season belonged to Romain Grosjean and his race engineer, Gary Gannon. The softly-spoken American joined Haas's F1 operation before it had even built a race car, over 12 months before Grosjean scored a remarkable sixth-place finish at the team's debut at the 2016 Australian Grand Prix. The pair found a workable dynamic almost immediately after being paired together, something Gannon believes has been a factor behind the impressive results scattered across the last two years of the Frenchman's career.
"It's everything," he tells ESPN about the importance of the driver-engineer relationship. "First of all on the technical side, we have a lot of the car but the feedback from the driver is essential to understand what the biggest problem is. I could go through all the data but that isn't going to tell me what's preventing him from taking a corner in a certain way, so that's essential.
"Romain is very technical and very intelligent so what he's able to give us is very thorough and very deep, so that relationship is very important from the technical understanding of the car side. Without those guys telling us what's what, there's only a certain amount a set of numbers on a screen are going to do for us."
The dynamic -- one which is different, with varying degrees of success, for each of the grid's 20 drivers -- is not as simple as a driver stepping out of his car and giving the first bits of feedback he can recall. Though the information itself is ultimately key, how the information is gleaned and communicated is an art form of its own.
"It's all about translations, various translations," Grosjean explains. "It's not an easy thing. For me as a driver I have to translate how I feel in the car to words, then translate that to the engineer, and then the engineer has to translate that into something which makes sense in terms of the data.
"The language you use and the level of detail you can convey is very important. I think the older you get, the better you get at making sure those translations are easy to make and you aren't giving feedback that an engineer doesn't understand. If you can't do that then you are going to struggle to get the most out of the package."
This need to find these translations can be a frustrating process, something Grosjean knows all too well. Were you to listen to every radio message broadcast on F1's world feed over the past few years, you would be forgiven for believing he has a short fuse when behind the wheel. His car-to-pit-wall radio messages are among F1's most frequently played because they are raw, often fraught; in 2017 Grosjean often appeared rattled by Haas' season-long struggle to master its tyres or understand its brakes.
But a bigger source of frustration was, as he sees it, a lack of understanding at how this crucial part of the relationship works and a belief his messages were singled out more than others. Journalist questions about radio soundbites quickly became Grosjean's least favourite to answer in 2017.
"I got pretty fed up of that pretty quickly," Grosjean says. "Every single driver probably says that and when they do, it's for the team, it's not for everyone to hear. I know I'm broadcast more than others and it makes it seem like I'm the only guy out there doing it.
"Gary and the team knows it comes from a place of wanting to improve the car and extract the maximum from it every weekend. If I felt I overstepped I go to see the guys and explain, but we all know how it is. If you had every driver's radio on all race, I wouldn't seem so bad."
Last year's U.S. Grand Prix was a case in point. After the race, audio of Grosjean venting repeatedly at the pitwall went viral -- mainly because of how it ended, when team boss Guenther Steiner's agitated voice replaced the calm Gannon's to tell the Frenchman, "shut up!". As Steiner would explain afterwards, a simple post-race conversation neutralised any ill-feeling about the situation.
Grosjean recalls the incident as one of the worst of that season, saying: "In Austin I was scared for my safety in the car at one point, because I could see the front tyre was gone more than it should have been. The team had lost the sensor so they didn't really realise the pressure, the temperature, or anything, so for me I was maybe more talking because it didn't seem like they knew what I was seeing. The translations [I talked about], we couldn't make them too easily and I felt I couldn't make them understand the situation I was in.
"I think it is easy when you're sat watching a race to forget that we're driving very fast under huge pressure, with lots of adrenaline, trying to convey the fact that the car is doing this or the car is doing that."
As Gannon explains, thick skin is required on both ends of such conversations. A big part of moving past any heated exchanges quickly is the understanding both of its participants are trying to achieve the same end goal: maximising performance of the race car.
"The thing that we understand is that it's not personal," he says. "We all get frustrated in our job and sometimes we blow up at our colleagues, it's not personal, we're in a difficult situation and things aren't going well and we're disappointed or frustrated.
"This sport is emotional and every time the driver goes out.... Maybe not reputation is on the line, but they're being judged alongside everyone else, so it's balancing those emotions with the feedback part."
Like his driver, Gannon believes the radio messages the world hears from Grosjean paint an unfair picture. The assessment he gives of the man who was Gene Haas' prize recruit ahead of the team's maiden season in 2016 sums up why many in the paddock believe he is still one of the grid's unfulfilled talents.
"One of the strengths is his ability to analyse data and the technical side. He has a thorough understanding of the systems on the car, which means he is very quick at diagnosing what's wrong and he's full of ideas of how to fix things. He's like an extra person looking at data after the session, so he really understands how to do that.
"He's very good with all the operational things, these cars are a real pain to drive and he straight away learns it. That makes my job very easy compared to other engineers who might have to be reminding their driver this, that or the other, so that part is very easy.
"Then on the other side, he demands a lot from us. Some of it you hear him being frustrated but he demands a lot from us and keeps us honest, but the reward comes from his ability to push the car to the next level. So every time he gets the car to Q3 or has a good race result, that's the time we are rewarded. He gets us to work hard for him, and he works hard for us.
"If the car can do it, he will deliver it. If the car can't deliver it he'll do everything he can -- sometimes it works, sometimes it doesn't. Some drivers can just find that remaining chunk of time [when they need to], Romain is one of them. Sometimes he'll get some runs bad, because he is trying to find where to run [the car], then he'll deliver a lap where we're shocked at the delta time -- so that's what I mean, he rewards the team with a great lap."