It does appear that the Red Bull is highly tuned to Verstappen's preferences, driving style and formidable car control because Pierre Gasly, Alex Albon and now Perez have all relatively floundered. Sergio's head may be wiser and more experienced, but he'll need to lean on every single element of that now to play his essential role and not crumble.
The only issue is that if Verstappen is closer to Mercedes in an edgy car than he is in a less sensitive car, the team will always chase the best performance from the package and develop the edgy car. It's a reality his teammate, whoever that may be, just has to deal with.
"It ends up being a dilemma because you are always drawn to the fastest time, that's just natural," Horner adds. "Sometimes the drivers aren't talking about the same thing [in engineering debriefs] and you will always be drawn to listening to the faster driver with the fastest time, that's just human instinct."
Gasly himself recently said he knows "exactly why it didn't click" during his time at Red Bull, but is either unable to go into details due to his Red Bull contract or is simply unwilling to dig up the past.
When those comments were put to Horner by ESPN, the Red Bull boss responded: "I've got no idea [what he's talking about], to be honest with you. Really no idea.
"He had absolute equality of equipment to Max. Obviously, Alex then got in the car and scored more points than him in fewer races."