I'm not sure if it's globally widespread, but Google Adwords has been making direct sales pitches to manage large brand's accounts, in competition to agencies. The pitch is generally, deal with us and you'll have more money to spend and we can do it better. Well they don't have to account for the same profit margins that an agency has, so it's likely they could be more competitive.
Often this goes with Google approaching and sometimes recruiting a person managing a major account, previously in an agency environment with added incentives.
Have any account holders, or agencies effected got a view on the relative efficiencies and risks.
In details: Google is trying to 'cook' and have the client ready for a bigger advertising budget he never planed to spent, and then, in a sleazy - one might say - move, they're switching to a local 'agency'.
Most of the local PPC companies (rather then freelancers), have the same/less experience then others, but they get the client 'from' Google, with intention to spent more then ever.
After watching 3 campaigns being updated/established by Google, I can say that they do great job, same as every PPC manager with 5+ years of experience would do (but, the budget and the intention to pay more - 'cause its Goo-fucXXng-gle' - are there).
And that's a 'Plus' for Google. not for the client.