Considering that the W03 gave Mercedes their first victory, and got Schumacher a pre-penalty pole position in Monaco, it was obviously not too shabby of a package, in terms of raw pace, in the early stages of this season. It’s clear that Mercedes then lost the plot in the mid-season development race, and now they have a car that’s sitting in the gulf between the frontrunners and the midfield, unable to live up to it’s potential.
Remember when Ferrari announced that they would be “revolutionary” with the F2012? They ended up with a shopping trolley for the first few races, and only got to their current level of performance with extensive redesigns from Spain onward. Seeing how they’ve fumbled with the W03, can Mercedes manage a similar turnaround if the situation arises?
Like @raymondu999 mentioned, a new car would just lead to more problems. With a “revolutionary” redesign, the team would have to contend with technical gripes, adapt to the new car’s setup characteristics, handling and aerodynamic quirks.
Ross Brawn must surely remember Rory Byrne’s old motto: Evolution, not revolution.