I would have claimed the entire payment on the husband's return, but that would have resulted in the wife owing tax.  (Which happened anyway.)  On a joint return, even without the UCE, they would have received a refund.  I didn't want to tell them to pay something in April, then wait until December for a refund.  

IRS clerks are supposed to know how to split ES payments.  They just didn't want to be bothered.