Butter cream frosting question:

[Tamsen]

All my life my mother made homemade butter cream frosting. Her recipe has the usual mix of butter, powdered sugar, vanilla and milk. But her recipe also called for one egg yolk. It's not a cooked frosting so the yolk always was a curiosity to me. The frosting turns out perfect every time so I've never questioned it.

But I'm making a cake for work tonight and I'm wondering if people would enjoy it as much if they KNEW it would contain some uncooked egg. Of course I could just not tell them. Still....I'm debating if I should leave the yolk out. I hate to mess with a recipe that ends in perfection.

Much of cooking is really just tasty chemistry. The butter makes it creamy and the powdered sugar really binds it all together. I can't tell what the yolk does in this recipe though.

Should I stick with what works or modify to suit the masses?