Newbie with a question. 
 First some back ground:
 I just had my first reserve ride on my 69th jump.
 The reserve ride was in reaction to a broken left steering line. The canopy did not look right-didn't wanna risk landing it this time - I say this time because 2 months ago, on about my 58th jump, I broke my right steering line. I rode down with rear-risers at the time, as the canopy was controllable. When I sent it off to get fixed, my rigger told me the trim was in great  shape for an older canopy (1989 PD 230) 
 So how is it that I keep breaking my lines on a canopy with good trim? It seems that the opening is really hard in both instances, but that might just be because of the line break. That snaps it around a bit.
  I always put the slider up, and flat pack it the same. I'm certain this is my fault and is a packing problem of some kind.  I'd appreciate perspectives anyone has on it.