dextrin malt is used for head retention. oats are an adjunct used for mouthfeel and head retention. im not sure adding oats to a smash makes it a smash any longer. what are you using the oats for?? if youre using them strictly for head retention, might i consider flaked wheat or carapils (dextrin malt) instead. both of these work better than the oats for head retention. generally you dont find oats in too many recipes, except for say a belgin wit, or oatmeal stout.