> I don't think I am giving anything up by skipping them My understanding is that there are some lock-free algorithms that we do not know how to write without

> I don't think I am giving anything up by skipping them My understanding is that there are some lock-free algorithms that we do not know how to write without garbage collection [Keir, 2004], so you strictly are giving things up, because you can't use those algorithms. (But I'm not completely up to date on latest lock-free work.)