I've never seen it done, and even with my basic understanding of WHS I don't know how it could done (without many many general play cards being used). It was mentioned earlier in the thread by another poster as happening to his handicap, so assumed it was something quite common.
I don't take that much notice of the maths involved in handicap calculations but given you are averaging over 8 cards, surely dropping one score isn't gonna change that much in your handicap. I don't get what range of values you need to move from 18 to 19 to 20 in just three cards.
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