Omiting salt in baking recipes that use chemical leaveners?
I completely agree with Cascabel's answer. I do want to add a bit.

Salt is an amazing flavor enhancer and most (sweet) baked goods use very little (1/4 to 1 tsp) considering that most of the recipes make 12-24 servings (more for cupcakes/cookies etc)  but it does make a difference. Most baked desserts gain quite a bit from having the added salt... and they don't even have to be baked.

Even in things like buttercream frosting, adding a little salt greatly helps to balance the overwhelming sweetness of the frosting and makes it more palatable to adults. All of my favorite buttercream recipes have a small amount of salt.

Anyway, removing the salt won't cause the recipe to fail... I'm sure I've accidentally omitted it several times in the past when I'm in a rush to get stuff in the oven... it can just make the flavors not as strong or remove some of the flavor contrast, so things can taste a bit flatter.