Gilbert Quevauvilliers figures out how field parameters work:
In this blog post I want to give a visual representation as to how field parameters works and what the current limitations are.
It is important to be aware of the limitations so that you do not get caught out later or you are trying to figure out why it is not working.
I do hope my descriptions and pictures below help you understand how it works and when it does not work!
Click through for some detailed graphics and explanation.