In general, most oil entry into the combustion chamber will be much increased when on overrun, i.e. slowing on a closed throttle, or mid gearshift, as the vacuum in the chamber during the intake cycle 'sucks' in oil from week points.
When idling or accelerating the combustion gases will do the opposite and prevent oil entry.
Thats why its a good idea to get someone to follow you and, by phone, tell you when they see smoke i.e all the time, on accel, or decel etc.
330i gone. 335i gone. E63 gone. M6GC current...