The 401(k)s and IRAs are commonplace. They are simple to establish and many clients have them. And while most account-opening forms are understandable and seem innocuous, naming the beneficiaries of retirement accounts is often not straightforward. Retirement account beneficiary designation forms offer little assistance and gloss over critical tax and administration issues by blithely advising “consult with your attorney.” Prior to responding to a client’s inquiry on “how to fill in the form, …