I was assuming that it was a one-time discount, which is fine. My assumption on the use of it was this:

If I have $6 worthe, then give $1 discount. If I have $12 worth, then give $2, and so on. I even tried reversing it, putting the higher levels first, but I still only ever got $1 discounted. I only want the discount to apply on groups of three, and it's $1 off for each group. Make sense? Can I do this with the current module?