That's a good approach overall. Thanks for sharing. There are a couple of problems with sales however:

1. In a way they address a different psychological need for people. It's about getting a good deal or a discount over the "normal" price, rather than considering the price itself... So you're testing different things that in some way conflict.

2. Over time, if people see there's always a sale, they might hold-off from buying?

3. It just gives a slightly "cheap" reputation (think shared hosting as a rather extreme example that comes to mind, or any site that always has tons of coupons on coupon-hunting sites).