I still think that Sandy used other housemates in an attempt to "divide and rule". Alex was his stooge, Adele would have been, Jade, despite being uneducated, was a bit too streetwise.

Sandy was finding it all too easy, got bored and left. Only Jonny, Kate, Alison and Sophie sussed what he was up to. He was probably the catalyst for most of the bitching and division in the later weeks.