Not in my experience. I've used this to get a job at one big corp and interviews at several others. The key is to contact individuals, who are often very open to answering questions about their expertise.
You aren't asking for a job, you're asking a _person_ to talk. Not listen to a pitch. Not give you anything. Just talk about their experience and what they see going on at the company.
Kai's Rule #1: People love to talk. They love to talk about their jobs, their struggles, and their opinions on the company.
Encourage them to talk. They'll tell you where the gold is buried.
