If you are going to use wads, the OP Wad should be used as is. It will push air out in front of it, through the powder, out the vent, or up through the nipple, and the hissing sound will tell you that the channel to the main charge is clear. The cusion wad can be " holed", but if you use just 1/3 or 1/2" the standard cushion wad, dampened with liquid lube/cleaner/solvent, you should not need the hole in the cusion wad to relieve air.
The OS cards are the ones that need the holes, as they do " bounce " on you, and then let air turn an edge to escape, and that is not good for patterns. Use 2 OS cards, as recommended by Jim Rackham, last Summer and Fall in his postings. Just line the two cards up so that the holes are NOT lined up together. They will let air escape through the wads out the barrel as you load them down the bore, and they will cause the cards to separate and fall to the ground after leaving the muzzle when the gun is fired.
Jim only uses OS cards to load his Fowler. 4 Os Cards instead of an OP wad, and cushion wad. Each is pierced, and he lines the cards so the holes are at 3,6,9 and 12 o'clock. He puts a ball or dab of lube between the 3rd and 4th cards before running them down the barrel. Then he puts in his load of shot, followed with two OS cards on top of the shot. The holes in those two cards are set at 12 and 6 o'clock. The holes allow the cards to quickly brake, separate, and fall out of the line of travel of the load of shot, so the wads do not bump the shot in the air, causing donut hole patterns. His patterns show a very even distribution of shot, using this technique.