Daily Telegraph: Interview with former Iranian Embassy hostage

Gunman and two hostages killed in Sydney siege: latest

Three dead - including gunman Man Haron Monis - and four injured as shootout ends Sydney hostage siege at Lindt cafe

16.58 Simeon Harris, a former sound recordist who was held hostage for six days during the Iranian Embassy siege of 1980, has spoken to Rory Tingle, who is following the story from London for us.
Mr Harris says the captives may well have formed a bond with the gunman during the crisis.
He told The Telegraph:

You do feel it is like you inside versus them outside. You are trying to negotiate the settlement, all of you – the hostages and the hostage takers – they will bond in a Stockholm syndrome sort of way. He might lecture them on why he is doing this, and they won’t tell him to stop because they would be shot.”
 
During the Libyan Embassy crisis, Mr Harris pleaded with his captors to allow the hostages to leave, saying that this would allow them to get publicity without causing bloodshed.

He thinks a similar scenario may well have unfolded in the Lindt café.

There was probably someone, or a small group, who came forward to negotiate (with the gunman) at some point. It would be someone with leadership skills, possible like a journalist – as the café is very near to Channel Seven – who will try to interact. 
 
You go into complete terror; it is as though you are involved in a dreadful film.
People would also have tried to bond with each other, as your natural instinct is to find someone you can trust and talk to.”

http://www.telegraph.co.uk/news/worldnews/australiaandthepacific/australia/11293694/Islamists-take-hostages-in-Sydney-cafe-siege-live.html