>> 2) especially, the fix is not 100% safe unless I'm mistaken.
> 
> What do you mean by "100% safe"? It is 100% deterministic (which is what 
> I care about); I'm not sure what you mean when you use the term "safe" 
> here.

It is not.  Whether the low-priority process actually starts depends on 
external factors.  If you have two priority-40 processes, they might 
prevent the priority-39 process to start and resume the forked process. 
  Of course, unless I'm mistaken.

Paolo