I know you're looking for opinions from custodial parents here... but your statement above, like some others I've seen on this board, completely discredit the role of the stepparent. It seems a lot of people here have forgotten the fact that stepparents are parents to your children.
We love and nurture, mentor and disclipine. We teach your kids how to tie their shoes, brush their teeth and ride their bike. We read stories and kiss boo-boos. Just because we are not blood related, does not mean that we are not extremely important people in your childrens' lives. We deserve your respect and the chance to build on our relationships with your children.
I understand that is probably hard for a lot of people to grasp. We are usually seen as a threat, like we are trying to replace you. It's not personal. We just want to be the best step MOM or DAD we can be when for your child when he or she is with us.
" how many of you would be willing to be denied time with your child(ren) to promote a relationship with your ex's new spouse"
Most non-custodial parents get every other weekend with their children. That's 4 days out of the month, leaving the custodial parent 26-27 other days. The fact that a CP would throw a fit over a weekend with the "new spouse" is sad. And who's to say it's a new spouse? What if this "new spouse" has been around for years? Would you still have a problem letting go of your child for a mere 48 hours then? It's so controlling...
*disclaimer* I understand that not all stepparents are created equally. My opinions above are just that, and are not necessarily the opinions of other stepparents. Have a nice day.