Look for the guy with a hammer
The old adage is that for someone with a hammer, everything looks like a nail.
It's a warning that people who are only good at one thing often believe that the one thing is the answer to every problem. And it's a good warning.
But what if you've decided that in fact, a hammer is exactly the tool that will solve your problem? My advice: hire a guy who only uses a hammer. Odds are, he's pretty good at it.
If you need cognitive behavioral therapy (the technique proven most effective for many conditions), don't go to a therapist who does six different kinds of therapy, as needed. Go to someone who has only one tool, but uses it beautifully.
Don't go to this person for advice about what sort of therapy you need. You need a generalist for that. Go to this person for her hammer.
If you want a piece of handmade furniture made with hand tools and hand finishes, get it from a craftsman who owns no power tools. And think twice before buying SEO services from a general purpose ad agency.
It sounds like I'm endorsing specialists, but that's not really what I'm doing. What I'm proposing is that when you're forced to choose (as opposed to mix or compromise) your tactics, it pressures you to make better stuff and to make better choices.
This is why the Journal's report that Google is flirting seriously with a big advertising buy is so troublesome. Once you start buying TV time, you just added another tool to your marketing belt. Now, plenty of your development and marketing team will say, "Oh, we'll just buy ads. People will use it!" Suddenly, you don't focus so much on building word of mouth and remarkability into your products, because now you can easily use TV to spackle over less remarkable products.
Bad news for an organization that's so good at one thing (building remarkable products that spread virally) to start pivoting into an area where they're likely to be not-so-good. This will lead to TV-friendly products that aren't viral, along with ads that aren't quite good enough to make them pop. By diversifying their toolset, they'll get less good at their core skill.
Choosing your marketing tactics drives the products you design just as much as the products you design choose your tactics. By having the discipline to run no TV ads, Google forces the organization to use the hammer they're really good at. More tools isn't always better.