Unfortunately Mercedes, Honda and BAR have wheeled that old chestnut out every year for the last decade.
It was true once, and that was on what has been coined the most expensive F1 car in history, but every other year has followed the same pattern...early promise, little to no development and then it's soon time to bring out the "We're concentrating on next year's car..." line again.
I'm almost counting the years to 2015 already...
This. Mercedes the team are really not that different to Honda the team. Brawn took a chance on the DDD for 2009 and it worked to devastating effect but when everyone caught up and found new innovations the team once again fell behind. It's probably fair to say that the main reason they were competitive at the start of 2012 wasn't because they had a genuinely fast car, but because everyone else was finding their feet still. Once McLaren/Red Bull/Ferrari/Lotus found those feet and brought newer pats to the table Mercedes simply fell back like a stone and couldn't keep up.
I think people forget that Brawn isn't a car designer. He didn't design the 2009 Brawn, his design team did. A lot of that design team have since gone. He might be a master strategist, and even that has been lacking this year for Merc, but he can't do everything. They might be banking on the 2014 rule changes but unless they have some kind of DDD like trick then they could be on a hiding to nothing because every other team will be making just as much effort to get it right. Just because Mercedes might build a good engine doesn't mean they'll build a good chassis. Look at Red Bull and Caterham, both Renault engines but one has just won the WCC and the other hasn't even scored a point. The engine probably won't change much. It's down to the chassis and the aero. Mercedes have a lot of work to do. There's also the question of reliablity, something that has been a big problem for Hamilton at McLaren this year. The last time Merc built a whole new engine was 2005/6 and it blew up. A lot. Hamilton may have to be a patient boy.
To me Merc look to be a team in the same shape as Toyota and Honda. Always promising, never delivering. Big changes are needed for them to even stand a chance of fighting for titles and yes signing a driver of Hamilton's quality shows they have a bit more ambition than Honda (they signed Barrichello, Button was already part of the furnatire) or Toyota (Ralf and Trulli?) ever did. But they need more than just a star driver, because without a decent car a star driver just looks like a driver. I hope for Hamilton's sake the Merc design team have a few tricks up their sleeves for the next few years or he could be in for a very tough time.
Then again they could get it all spot on at just the right time and waltz to both titles. But history suggests otherwise.