Also, I think we should decidedly not support "offsets" from the price feed, as this loses easy parity with other tracked buyers/sellers. The only way to match these offset-tracked orders would be through normal limit orders (other than using the exact same offset, of course) which is at odds with this feature's intended benefit- reinforcing the peg. It's also a lot easier to implement without this, both core/UI wise.
If you don't allow an offset you can support the peg only on one side, because orders from both sides would cancel each other out.
Also, why should market makers place orders *at* the feed price in the first place? They'd take all the risk but can't make a profit from it.
If you want to support the peg, allow offsets - this will create competition among market makers, which means more liquidity, and with more liquidity market makers will be forced to use small offsets.