The answer may be spot on but it's still terrible state, and ought to be fixed properly. From an application security perspective, account sharing is bad. Every user should be able to have their own account and cooperate on a joint return, so TurboTax can tell who did what. Sharing account info increases the likelihood that information is intercepted. You have no non-repudiation. If both people say they aren't responsible for an action, TurboTax can't say who did what: someone could be lying or the account could have been hacked. Who knows? In this day and age, there is no excuse for not supporting one account per user, even if they are cooperating on a single return in the application. It would obviously require extensive rework to properly support, so they're just being cheap, and compromising the security and function of the product as a result.
