We had a XC event last friday that included running repeat miles, I did three for the first time in about 2 years I think.  All of them were 5:15 or lower.  More importantly, my hip felt great, I do think my left knee is taking the brunt of the workouts though so I need to make sure I take my time coming back.  But I've only done one speed workout and on my third try at the mile during the event, I hit a 5 minute mile and I wasn't hurting either.  Just a little tingling in the arms but nothing difficult.  So that was very encouraging.  I don't think I'll be breaking 33 in the 10k for awhile but hey, every little gain makes me feel like a comeback is possible.