Is this really an effective recruiting tool? You don't even know if I am any good at my job. And since you don't know if I am any good at my job, you don't know how much you're going to need to offer to make a move tempting. IF the work is remotely interesting (It often is not) I respond with questions about location and salary range. It has always died at this point. Usually the top end of their salary range is significantly less than I already make.
I've only ever been successfully poached by companies/managers who know me and have worked with me in the past. They know exactly why they want me and have some idea what it will take to convince me to jump ship.
I think it would be hard for both employee and employer to take a big risk and hire/be hired blindly. Especially for high compensation individuals. What if I'm not actually worth what I'm currently being paid? What if I jump ship and discover that the new company is not great to work for? Seems like a lot of risk for both parties.