A couple of months ago I double dropped a batch of beer. I really was just moving a fermenting beer because I had brewed a couple of days before my fermenter was available and started fermentation in my kettle.
I was surprised that fermentation really sped up after the transfer and was very vigorous. That time I just poured between buckets like it was a bucket of water.
Since then, every batch I have waited 24-36 hours after pitching yeast and then opened the fermenter lid and stirred up the trub on the bottom of the fermenter and agitated the surface to aerate a bit.
Every batch I have done this with has sped up shortly after. I am regularly getting very vigorous fermentation and regularly getting to FG in about 4 days from pitch.
I have kegged many of these batches at the 7 day mark.
I’ve done this at least 7 batches; lagers and ales. I have done it with Diamond, 34/70, Bry-97, and Verdant IPA yeast. All of the beers have been great.
Just sharing my experience.