Why is Self=Null wrong?

[code]
Type MyEntity
Global _list:TList
Field _link:TLink

Method New( )
_link = _list.AddLast( Self )
End Method

' Of course, you also have to nullify your reference to it then call FlushMem. But this gives you a chance to free any other resources.
Method Dispose( )
_link.Remove( )
End Method
End Type