For all the big commercial grows it's lights on lights off.
Plants that never throw balls would not have any problems switching quickly.
Some plants are sensitive to stress and throw balls.
I don't know if there is information on there being affects on plants that are more prone to hermie in early flower.
I like doing it gradually with my 2 600w hps.
Makes me a happier grower I suppose and for me it's about enjoying my room.
A similar topic is should you go from 18/6 to 12/12 quickly or gradually.
I take it a step further.
I have the 1st light come on 15 minutes before the 2nd light.
At lights off the same thing.
Lights come on and off from the east sunrise to the west sunset.
Call it crazy. I say no harm no foul or Good Karma.
Happy Growing!