public override bool RemoveAt(uint index, uint count, IAListTreeObserver <K, T> tob)
{
Debug.Assert(!_isFrozen);
if (tob != null)
{
tob.RemovingItems(_list, (int)index, (int)count, this, false);
}
_list.RemoveRange((int)index, (int)count);
return((_list.Count << 1) <= _maxNodeSize && IsUndersized);
}