Please let us know how this works out; DH and I were in that position for years (in our case, he had SS and I was working) and filing separately never made sense to us. Even if I allocated just enough of the deductions to him to get his Federal taxes down to zero, my side of the taxes skyrocketed. Our state marginal rate wasn't bad so I figured that wouldn't make up the difference.
Keep in mind that you and DW both have to itemize deductions or neither can itemize. That's because if, for example, you take all the deductions and DW takes the standard deduction, she's getting an "extra" deduction and that's not permitted.
The only time Married Filing Separately worked for me was with my first husband in NJ; the $$ we saved on NJ taxes was worth it. I also filed separately the year we were separated prior to our divorce, knowing he wouldn't file and wanting to keep my own record clean.