I will speak from experience.
I have had instances from seed to flower where no mist was applied AND I have had instances where I misted every 2-3 days, heavily, up until 3 weeks into flower. I must say plants grew quicker, looked healthier, and overall were more vigorous with mist/rain than the exact same genetics under no mist/rain conditions. I always misted during the 'day' BUT would use ambient lighting during the 'misting' (hps/mh lights off!) and have a 2-3 hour misting period where you go in there every 20 mins and drench the girls. I used the ambient light to avoid quick evaporation and let the girls rest a bit and drink, I suppose the ambient lighting could also simulate thick clouds on a rainy day. All misting done coincided with either a light or full watering (my own watering method, i.e. light & full watering).
Whoever said to replicate what you see outside... You hit the nail on the head.
Though a plant will grow without being misted this doesn't mean it shouldn't be. All plants have evolved, for hundreds of millions of years, with rain as part of their lives (for the most part) so why deny them what they've evolved to tolerate, accept, love, grow better with?
There are definitely times you do not want to mist. This would be when flowers have grown to the point where water can no longer easily evaporate from between them- doing this will avoid any issues with mold. I would also recommend not misting at night- not because of mold but more so because you'll likely interrupt the light cycle.