Automating Agent Pooling

We have a large number of jobs - an impratical number to use the front end to associate with agent pools.

I think this is something that would be easily acheived by a bit of SQL in the database but have been playing with it and am missing something.

Here's what I am doing:

1. Adding new agent pools into TCDatabase.agent
2. Modifying the agent_pool_id in TCDatabase.agent_type to move the agent to a new pool.
3. Distributing the jobs across the pools using agent_pool_project.

But it's not working correctly. Can anyone give me a steer?