Frank and I have been talking strategy -- how to potentially use the investigation to set something up -- and Saltash came up as a possibility.

We could make MLE think they've got access to Saltash, and then overpower everyone who comes through the barrier. They'd concentrate their energy on breaking into a larger safehouse, possibly taking the heat off of their current investigation. I believe that none of them know about the properties of Saltash yet, and they would be taken completely by surprise by the null field.