Re: Ventilation holes - a good idea?
Now that you have drilled them, leave them open. AS was already stated, the bees will close them up if they wish.
A proped up cover/inner cover w/ a cinder block on top requires quite a heavy wind to blow off of the hive. But I see holes in hive bodies all the time and have purchased lots that are that way. Never drilled a hole in a hive body or super myself tho.
Just because something is new to you, doesn't mean it is new, or revolutionary. Mark Berninghausen