The terminology "not considered unmarried" is a double negative, but that is the terminology used.  See the "Married Filing Separately worksheet" on the 2441 form.

In my case, my taxpayer is married.  Both he and his spouse earn 6 figures.  He has 2 kids that he is claiming and $5000 in box 10 DCAP on the W-2.  If he was "considered unmarried" then he could claim the whole $5000 of DCAP.  (He can't get the child tax credit, but he could use up the $5000).  In other words, it's like he's single.

My client is definitely.  The most EACH SPOUSE can get is $2500 on their individual tax returns.

Since he had $5000 in DCAP, he should wind up with $2500 added back into his wages if he files MFS. The software is NOT doing this.  

I am happy to walk somebody through this and send them the sample return and they'll see the problem.