Traditional Situation-Based Interview. Situation, Task, Action, Result.... Until the last interviewer I met with. He deviated from the standard process which is typically not allowed within larger organizations because it risks introducing partiality which could create other issues requiring HR involvement.
I may actually consider sending an email to Exelon's general HR department to provide them with a synopsis of my experience including the final interviewer's name. This is a learning/training opportunity which could be used to protect the organization.