I know from a pretty good source that easyJet Switzerland (not easyJet) approached SOU and basically told them they were coming in. No negotiation at all. It was all operational in nature.
I think emotions are running too high here though. I am a fan of BOH but I do see the potential at SOU to be complimentary to whatever LCC stuff goes on at BOH. Between SOU and BOH they should together be running at similar levels to BRS (8m pax per annum). SOU will struggle a little with LHR 3rd runway, so it's imperative that they start to get traction now.