Symbolism aside, if government extended marriage to same-sex couples, the new spouses would find the pros and cons about the same.
Marriage is the same for everyone, regardless of the sex of the spouses. 
mnli hypothesis: Marriage is the same for everyone, regardless of the sex of the spouses.  premise: Symbolism aside, if government extended marriage to same-sex couples, the new spouses would find the pros and cons about the same.