At least banning it now, is better than banning it half-way through the season. From the wording of the rules and the way we've been told the device operates it does seem pretty straight forward.
But insiders say that, once it became clear its main role was to improve aerodynamics, banning it was a "no-brainer".
Article 3.15 of the F1 technical regulations requires that any aerodynamic effect created by the suspension should be incidental to its primary function.
It further states that any device that influences the car's aerodynamics "must remain immobile in relation to the spring part of the car".
I guess we could raise questions, about FIA consistency and competence, as they initially stated the device was legal.
The two teams were initially told the device, which aims to keep the car stable during braking, was legal.
But following further investigations, and representations from rival teams, the FIA has changed its view.
Rival teams trying to get innovations banned is nothing new, and hardly unique or even led by Ferrari. You could call into question why the FIA need it pointed out to them though, shouldn't they, in the majority of cases, be able to stand by their own decisions? But of course F1 cars and the rules are complex.
In terms of consistency, with the blown diffusers issue, it was something the FIA declared legal, then illegal, but decided to wait until the end of the season to ban it .Not quite comparable this time as it's pre-season and pre-pre-season testing), and with the blown diffusers all the teams agreed to let it slide.
I'm guessing a legal challenge could also work in reverse? If the FIA banned something that the teams thought was legal, we've seen legal challenges in terms of the FIA allowing something that some teams thought was illegal.
The most interesting point was this:
An FIA insider said Lotus and Ferrari seemed unconcerned at the decision to ban the device
Maybe it's simply subjective bias, Lotus and Ferrari won't tell the FIA how important it is to their car, it's irrelevant, so maybe all we can infer is that they were expecting the decision and don't feel like challenging or protesting it.
Or maybe they're working on an alternative, legal version.
Or maybe it wasn't that important anyway. Thanks to stringent rules, innovation is now relatively rare in f1, so it is picked up on and over emphasised any time it comes up.