When do we access those weak ties

Andrew McAfee gives a little more thought and background to how to justify social networking services, whether it is a Facebook-in-the-enterprise or blogs or something else in The Ties that Find.

In fact, the concept of an option is a useful one for understanding the overall power of weak ties. An employee’s strong ties give her colleagues. Her weak ones open up options. Technologies that help weak ties proliferate therefore also provide options. Given how cheap they are, and how many options they bring, they seem like one of the best investments out there.

So, we have technologies that open up our options.  How do we talk about when to access those options?  Obviously, the whole point of weak ties is that they are infrequent.  But how does one know to move away from the strong ties and implore weak ties for help?  Is there a "process," or do you rely on random colleagues coming across your questions / problems / etc?  Or is there some other mechanism.