Flaked oats in a dry stout?

At the beginning of January, I'm planning on making a case (or maybe two) of classic Irish dry stout for St. Patrick's Day. I've had good results with stouts I've brewed before, but I haven't yet tried to full-on replicate a dry stout like Guinness. The biggest barrier I'm foreseeing right now is my inability to nitrogenate, and as such I'll lack the signature smoothness and mouthfeel I'm looking for.

So besides carbing to a lower level, my only idea to compensate would be to use a portion of oats. I've had commercial oatmeal stouts before, but I've never brewed one, so I'm unsure of the oats' effect on the beer's other principal characteristics. Will adding oats to the grain bill affect the dry character that I'm going for, or would this be a reasonable method to replicate a classic Irish stout?

In my experience, the oats shouldn't affect the dryness of the beer. It will, however, add more mouthfeel and body.

+1 I agree, very little added dryness. But it will add that "chewy" mouthfeel.

Most the time dry stouts use a higher percentage of flaked barley for the mouthfeel/creamy-ness not oats. The rest is pale malt and roasted barley. An easy and tasty recipe is 70/20/10 Pale Malt, flaked barley, and roasted barley

If you want a dry stout use flaked barley. If you add flaked oats, well then you have oatmeal stout. 70/20/10 tends to be what dry stout recipes a measured against. This just happens to be my next brew.