Smoky Rolls-Royce engines on Delta 757

It's worth mentioning and wondering aloud in the websphere: does Delta or Rolls-Royce do something different with engine maintenance that makes for hard, smoky starts?

i've noticed over the years at airports from one coast to another that Delta RB-211s on L-1011s always started amidst huge puffs of white oilsmoke. I was told by some veteran pilots that this is normal for the RB211 on an L-1011 - especially near the end of the 'plane's useful lifetime, as Delta's aircraft were.

On Christmas eve, Patrice and I took a Delta 757-200 to Atlanta on the way to Baton Rouge. After pushback from the gate in San Francisco, the engine start seemed to take longer than the normal 30 seconds or so, and some shadows drifted by in the early morning sunrise light illuminating the cabin. Seated aft of the wing, I had a good view of the right engine lighting in a smallish puff or white smoke - and a not-so-great view of the left engine lighting in a HUGE and protracted steam of blue, then white smoke.

So, any pilots or turbine mechanics out there have insight? One would think with turbines that this might be a wet start caused by an oil overfill during overnight maintenance or an overly rich mixture keeping the combustion chamber cold during start. I understand that with the original RB-211s on L10-11s, the white smoke on starts was due to oil gaskets cold-soaking while the ket sat at the gate.