I agree with this.
When Mercedes bought into the financially ailing Brawn GP team, they misjudged the situation and continued to run the team on a shoestring budget.
They realized too late that the team was in complete shambles after the Honda withdrawal. They went from 800 to 400 employees (including engineers) within the space of a couple of months. The 2009 championship was won based on a full-on Honda assault led by Brawn starting when he arrived there.
The low-level funding went on until last year when they realized they had to step up.
It's too early to see the result of this in my opinion. Although I expect a better car for 2013, it will not be enough to compete with those who are already on a good development path. Unless they are saved by the new spec 2013 Pirelli tyres. The 2013 tyres will have a wider operating window due to a new construction, new profile and new compounds.
I know I am nearly alone with this, but it was the tyres that had broken their back this season. The car itself was/is very solid, and would be bloody fast if not for the 'delta-time' style of racing. They have tyre tested with the old config, to get extra development time. And in the end, that seems to have crippled their whole season. So the Pirelli-factor will be very-very decisive, IMHO, because if the new construction and compounds ( btw, is that a fact? I only remember reading about new compounds, and was thinking that will not be enough?) give them back what they lost they could be reasonably ok in 2013.