Purchasing Only1Visa with Discounted Wish Cards Via Platinum Edge

I am just wondering if many Ozbargainers do the above? With 3 points from purchasing discounted Wish cards from cashrewards with the platinum edge and even allowing for the $5.95 charge isn’t there a gain of approx 2%? Surely it is worthwhile buying the $100 Only1Visa by this method? Then use the card at places or even online where you will clearly gain? (By the way I am assuming that you will get 3 percent off the Plat Edge by selling qantas points at 1c per point). At most you gain 1% from a credit card point so you are 1% ahead by purchasing those Visa cards and using them in most places. I am curious to know if many ozbargainers do this? Of course you can’t do it with the ATO anymore which is a pity.