Evidence that the car was "built around" the other driver? That's trotted out a lot, but there's neither technical Evidence in the public domain nor confirmation from an authoritative human source. That's just one of those tropes that gets repeated ad nauseum.
Indeed, the likes of their detailed suspension layout, the almost motorbike philosophy behind the angled orientation of their wishbones, the aero, its all new and everyone is rushing to copy (except MB, who tried copying but weren't clever enough to make it work in the wind tunnel.) Thats groundbreaking, never used by any team prior to that so can't really be any drivers preference as nomone had experienced it before. It's clever exploitation of physics within the rules, and in the case of the suspension using geometry to gife an i gerent ainti-dive effect that that no one had ever thought of much less even tried before, not an attempt to design a car to specifically suit any one driver.
As much as Red Bull Spice annoys I have to show grudging admiration for him overseeing a team that simply fields a that can be effectively set up to work extremely competitively in any track environment. That's driver preference in the sense that every single driver would give their left nut for a car of their own that can do that.
Mercedes have been accused of that too during Ramilton's reign, yet listen to him moan about the car and how upset he is because the team didn't listen to him (so he says) about the design direction. That's hardly the talk of someone who has had a car built around him.
Fact is that excuse gets aired every time a driver is dominant for more than a year or two, its the excuse the fans hold dear as the real reason their favourite wheelman is a distant second. The real reason is that driver number 1 is simply more talented a driver and has a better understanding the engineering principles behind car set up, not because someone has spent tens of millions doing him a special favour.
We heard it for Schumey, Vettel, Ramilton, Max, and well here is again in the future when the next young thruster dominates and their very likeable but rather lacklustre team mate struggles to match number one consistency.
Set up and tailoring the car to suit the driver is a different matter entirely. Minor differences in seating position and control layout etc can be accommodated, and the same car made to behave very differently. Schumey was famously like Max in liking the car and controls and resultant response razor sharp and hyper immediate, yet Barrichello liked some progressive slop in the controls and response, most partially the brake pedal. That's down to driver preference and willingness/ability to push the limits of car behaviour.
In the case of Perez, as tidy a driver as he is, he's simply not as good an engineer as Max and thus unable to communicate as effectively to his crew, and his synaptic response rarely even peaks at the level Max operates normally. Riccardo is much closer to Max in both regards...or was at his peak.
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