I've tried poking holes in both bc and fondant cakes and still got bubbles.
What has really made a difference for me is making sure I press each layer firmly, then weight the cake while it rests for at least 4 hours, preferably overnight. Then, press a good, firm crumb coat (or spackle coat under fondant) on the sides before icing. If chilling is necessary, either 30 minutes in the frig or 15 minutes in the freezer - no longer.
Or, the blowout demons have just decided to leave me alone so it doesn't matter what I do.