What it should read is...'do not normally exhibit such volumes of smoke, unless the ambient temperature at the airfield is quite low, and the engine has been cold soaked.'
Very common to see these engines smoke on startup, under the above scenario.
In addition, also under these circumstances, a wing engine will normally spool up faster, during start.
The proximity of the number two engine to the APU is immaterial.
Come to think of it, that is the only time I have seen RB211 engines on L1011's smoke on start up. Does give credence to the labryinth seal theory though.
We still don't have a confirmation from what it smells like (fuel or oil) from somebody standing directly behind one though
