So as long as indicator is on you pull out regardless?
Not regardless, no. I weigh up the situation. You seem to assume that I take a black and white view that indicators are the only thing I assess.
If someone comes flying up to the roundabout at Mach10 with their indicator on, I don't pull out. I figure they might be intending to cross straight over and have left their indicator on. So I don't pull out.
If someone is slowing down, looking to their junction, turning in close etc, AND their indicator is on, then yes, I will usually assess the risk and decide that they are probably going left and pull out - usually, even if it is a mistake and have just left their indicator on, then the speeds are so low that we can both stop safely anyway.
But generally, I wont pull out
at all if there is NO indication. So it's incredibly frustrating when someone is approaching the roundabout slowly with their indicator off, but still turns left. I wait, because they could be heading straight on slowly. But their inability to take the effort to twitch the indicator stalk to reinforce my assessment that they are making a left turn delays me, and causes me to wait unnecessarily. Hence, it is a major irritation when their laziness then leaves me waiting for ages when I could have been gone.
So in a nutshell, I won't rely on indicators ON as a signal to go, but I will rely on them being OFF as being a signal to wait.