private static ClientOperation<T> Remove(ControlItemCollection items, int index)
{
	if (index < 0 || index > items.Count) // should be >= instead
		return null;
	var item = items[index];
	items.RemoveAt(index);

	var operation = new ClientOperation<T> {Item = (T) item, Type = ClientOperationType.Remove};

	return operation;
}