But what would the correction be and, as a practical matter, how would correction be possible? The money is in the plan, the amounts were not reported as income for any years, and the participant (presumably) hasn't made a peep ... even after having rolled over the whole account. Is the employer's failure to implement the participant's election to have amounts withheld and contributed as Roth an operational (qualification) failure if the participant essentially acquiesces to the tax treatment of his or her contributions by failing to notice that his or her Forms W-2 and plan statements reflect pre-tax contributions? Is the procedure for electing Roth vs pre-tax spelled out in the plan or incorporated by reference in the plan? In other words, perhaps there's a reasonable basis for arguing that there's no operational failure in a case like this.