Thanks for bringing my attention back to that project Oscar. Yes, it's true that the Fb will be shifted downwards significantly (sometimes quite so), when the port is located near to a boundary. This effect showed up in my project linked above, as you've indicated.
The increase in the system's bandwith though still has me a bit puzzled. Maybe port losses have changed because of the boundary effect? I'm not sure. I haven't had an opportunity to revisit that project - I think I will do so this weekend, to see if there's any way to account for the increased bandwidtth that I measured.
