Sure some are 'more fit' than others, but last I checked, you're never really fit enough to raise children. It isn't like someone hands you a step by step manual on how to raise children and the expect expenses that in which you will be facing. Really I'd say no one is completely fit to raise children, your children eventually whip you into shape
As for Carlin, a pity to have seen him gone, he was rather brilliant and he still manages to send me into a fit of laughter unfit for the wee hours of the morning. Though a few of the stats he threw out I feel the urge to check up on, the rest of the statements he made however I fully stand behind, probably with a smirk on my face.
Fact of the matter is adoption really isn't a good alternative to abortion. If the child is lucky enough to be given to good temporary homes until actually adopted, it still means they're shunted around without any real consistency or structure in their lives. (That's an 'if' I don't need to cite the horror stories that some kids endure in the system that is beyond broken) Not too mention, you're still throwing kids into a system that is overloaded, into a world that has so many children in it as it is. To me that really isn't pro-life, those kids may never have the chances to have a real life in their younger years, if ever, just to rot away in the cracks of the system.
For me personally, from what I heard from my mother, I could have had two other siblings, one older and one younger than I. Both my sister and I fell into a time in her life where she felt that the children being born would have had a stable home, a loving environment, and parents whom would be able to provide for them. She was right. The other two? No, considering the time periods that these children would have been born, my mother would have either been too young, or with the case of the later child, within three or four years would have been in a seriously harsh financial situation and WAYYYY on the outs with what would have been the father.
Her reasons were sound, but as I told her, reasons are inconsequential. In the end, your reasons don't really matter much, as it is your body, your choice, your decision in the end. Reasons only serve to justify where justification doesn't matter to your critics, and are redundant to the people who support you. So really, I don't think discussing the reasons, or the justified reasons, for such a thing have any real point.