Yes, but be sure to check "Apply community property rules" on Screen 3, and make sure that all income that you want split evenly (other than wages) is "joint."

Of course, you should always make sure that there's no pre-nup or other reason why you wouldn't use community property rules - like they were separated the whole year with no intent to reconcile.

Now, as to what the IRS does, that's a whole 'nother question.  My experience is about 10% of the time they confused by split withholding, and put a hold on a refund - usually the wage earner!

Also, if there were estimated tax payments made in only 1 SSN, there's about a 50-50 chance you will be on the phone with PPS re-allocating it evenly.