surely one small part of present-day penology ought to include the notion that - at some point down the line - be it 5, 10,  20 / I don't care how many years after one's sentence has been fully served ... 
any record which can be expunged is (otherwise, all we are really doing is encouraging the growth of an alternate society), for if there will never come a time when a record is wiped clean, how fair have we been really ?? 
in a case like this (in a mess like this) it's probably best to do what little you can, and with our 'never say never' attitude we have inherited, we haven't even met that barrier / 
you want a less tangled system than the mess you have now, either beat every other inmate 'half to death', or start playing fair with those ones who are reachable.