Hi - mine does the same thing but usualy the left side and an odd occasion the right side.
Not wet sumping IMO, probably oil leaking past the valve guides drains down (inlet onto piston crown - exhaust down into the exhaust pipe where it soaks into the carbon) depending how the engine stops will determine which side smokes.
Oil that gets into the exhaust pipe will soak into the carbon and take a while to clear, oil onto the piston will probably burn off more or less straight away.
Wet sumping would leave a little puddle underneath the engine or a large one if left long enough, some oil will always be left in the sump but the scavenging side of the pump should clear this fairly quickly if not then it would be blown out of the breather tube onto your garage floor.
Well thats my theory, your welcome to agree or disprove it, any comment welcome
All the best - Bill