Greg,
I have done this in the past when I needed to jack up CYA pretty fast. Since you have pucks already you can crush them. They pulverize very easily. I put one on a couple sheets of newspaper on a cement floor, cover with another couple sheets and gently hit with a 3# hand sledge. Hardly have to hit them to break them up. Then I chuck the powder in the skimmer and let the powder dissolve in the filter. Dissolves fast. I have a sand filter but have to say I don't know if you can get away with this with DE or cartridge. You get the added benefit of adding chlorine at the same time but watch your pH. It will drop.
Al