Well i read this whole thread (and i have to say, i KNEW when i read the OP it must have gone pretty off topic to be such a big thread! =o).
I am surprised to read that by Smithie's standards i don't have a family (i am personally opposed to marriage). I really thought i did! :lol
I have 2 kids, one with XP, one with DP.
You know what? The DAY XP ejaculated he really might have fit the "deadbeat" label. He was a neglectful partner, he was very unhelpful and not at all supportive in many ways through the pregnancy, birth and early days. I left him when DD was 4months old (having split from him and slept in a different room while hunting for a new place since she was 8 weeks).
When i left him he was: smoking pot often, not earning, not helping with caring for the baby unless forced, not assisting me at night, not interested in supporting me emotionally. He was on the birth certificate. To me (and him as it happens) the Birth Certificate is a record of the facts surrounding the child's context in the world. It is for the child and for the state. it is not for mummy and daddy to use as a weapon, get out of, abuse or misuse. It doesn't matter to me if a perfectly nice A. N. Other wants to raise the baby. The child deserves to be able to see the documented truth of their existence. Thus XP, her biological father, was listed as her father.
DD is 4.5 now. and XP is: no longer smoking pot, not earning (hey, recession! but WAS earning and still now pays 300% of his ordered support given his income), excited about his twice weekly overnight/full days and the other day when we meet up for him to have additional access (he sees her 5x week minimum), a loving caring involved father, a very supportive co-parent and very loving and beloved influence in both her life and the life of her sister, DP's DD.
DP has taken on the financial, emotional, mental and parental responsibility of DD1 too. They both act and regard one another as her fathers. In december they took her, together and without me, to the pantomime together. It makes me really really sad to think that i could have looked at the snapshot of how XP acted when he was still in the shock of becoming a parent (DD1 was an NFP mishap) and decided from that moment on he was worthless to her and us and ditched him. CERTAINLY he was not the right partner FOR ME. But to extend that to mean he was so worthless he shouldn't be allowed to be a father to his child is, just, horrible. Being a parent has been the making of me, the best thing that ever happened. Some of the hardest and most rewarding work of my life. It is the same for him. Was he excited about it? Did he make the "right noises" about it at the start? No. Did he have to be forced to spend time with her initially? Yes. But you know, when DD was 4 days old i shouted i was going to chuck her out the window at her during the 5th hour of screaming (she is HN!). It saddens me to think one could have taken that tiny glimpse of someone struggling desperately to cope with parenthood when it was all new and a massive challenge and just me unfit to love and raise my DD.
People grow and change. People develop skills and find enthusiasms within themselves they never knew existed. People who might have only "ejaculated" end up being fantastic fathers. I know because i have witnessed it myself.
To me conception can never be "fair". Men can't give birth and women can't walk away from a pregnancy. Men cannot submit to an abortion, they should not be allowed to force another person to do so. Of course it's not fair - how can it be? Spending time and energy trying to make it fair for the parents seems so pointless when we could be making sure it's fair for the CHILD. Do children ALWAYS benefit when a father is judged to be worthless and expelled from their life? No. Nor would they if we did the same with mothers.
Parenting and parenthood are messy messy things. We do not own our children, our children own US.