And what of people who don't want to leave existing full time employment for a three month contract that might turn into a job if things work out well? Similarly, I doubt most people would be willing to move to a city for a temporary contract.
Usually if people are looking around, they are pretty fed up with the place they are at for one reason or another. If it's a good developer, they would know they would make the cut, so they would take it if it were a decent company with decent pay.
Also, there is no distinction between a full time job and a temporary contract in terms of survivability in the US. Most states are at-will states, and not being able to do the work is a fire-able offense. Just about everyone knows this.
Most people who have been in the business a while aren't willing to move to a new city, again unless you are willing to pay ungodly sums of money. If you are hiring right out of college and junior-mid's, this technique is better suited, but still, you're competing poorly in a seller's market.
I mean, just because you are hiring and paying a salary doesn't mean 20 other companies in your area aren't doing the same. What makes you better? Certainly not market rates and certainly not your exhaustive and mostly ineffective interview process.
You want a good person, ask your tops if they know anyone good, then try to lure them away with an offer of 1.2x - 1.5x market rates, depending on the return you expect from them. Trust your tops and don't put them through this silly process. Have the top interview them with you in the room. Spend about an hour with them to make sure they aren't some weirdo. Trust me, they'll respect you more if you respect their time.
