"If it got to the point that a child was causing disruption in my class I would deal with the disruption in whatever way was most effective and least disruptive to the rest of the class, that may in a limited number of occasion mean removal."
Absolutely agree with this.
Removal can be immensely disruptive to a class - much more so than an original disturbance. A couple of quiet reminders while the class is engaged in some other task - doesn't disrupt the class at all.
Equally you have to remember that some children, knowing that they would be sent out of class for a minor misdemeanor, would actually choose this easy way out rather than the harder (for them) option of staying in class and working at that particular subject. Having a 'predictable, robotic' response with no judgement from the teacher would result in such unwanted side behaviours. Genuine, proactive behaviour management tailored to the class and child and occasion does not.
(On my point about statemented children with slightly 'different' rules above - I think that you missed my point about them being statemented - ie they are children with very significant special needs in terms of physical, sensory, behavioural and learning impairments. One of them cannot sit still on the carpet, because their physical impairments make this very uncomfortable - so they, only, may sit on a chair. Another has very significant visual impairment - so they, only, may talk to their 1 to 1 worker to interpret what is on the board. That was what I meant by 'changing rules'. None of this will prevent others reaching their potential - and actually the educatuonal and social benefit in terms of lack of prejudidice, taking responsibility, appreciating others for what they can do rather than what they cannot [did you look at the Paralypics and say 'well, those athletes must have been preventing others reaching their full potential when they were at school'??] it is invaluable.