Q01 for Bryan: What's Necessary?

Bryan - Thanks much for spending time on this blog with me.  I have 5 questions which I have been asking people on you side of the discussion for about a month now, so I'll pose them to you.  This is the first one.

I'm willing to concede D.A. Carson's reading of 1 Cor 12-14 for the sake of this discussion. Given that concession, isn't the more critical question whether or not they are necessary for the life of the church? Why or why not?

I’m not familiar enough with the particulars and nuances of Carson’s individual take on I Corinthians 12-14 besides the fact that I’ve heard it is supposed to be the best treatment of those chapters in favor of continuationism but with an apparently stronger exegetical to practical work in keeping the “Love Chapter 13” understanding and application in the context of the gifts. I’ve been meaning to read it but haven’t yet. I almost bought it last night on Amazon so I could say I’ve read it, but, seriously…I’m not sure when I could dive in to that right now. So I can’t honestly say that I would then agree, the more critical question to be whether or not the gifts are necessary for the life of the church because of your concession to Carson’s interpretation and applications.
However, I am glad for the conversation to take a different direction than re-hashing the arguments over those chapters. So compared to doing that, yes I’d agree, if we’ve both agreed on things like--that Paul teaches us in the context of I Corinthians 12-14 that each is given the manifestation of the Spirit for the common good and that we are to pursue love and earnestly desire these gifts, especially that we may prophesy; and by implication to not do so would constitute disobedience-- then of course I’d agree there are more critical questions to ask. But I answer no to your question because to ask whether or not they are necessary for the life of the church would be rather unnecessary by virtue of what we already have agreed on about the passage.
Why would Paul command something that was unnecessary?
Why use passionate language like  “pursue” and “eagerly desire” for things that are potentially unnecessary?  
If the Spirit’s gifts/manifestations are still valuable enough to the Spirit and in Paul’s mind to “risk” commanding an audience who had been abusing or misusing them- to still yet eagerly desire them for the building up and strengthening of the church, then that tells us how important Paul knows these gifts are to God and to the church when done in love. The fact Paul is even addressing the abuses with commands to pursue love and maintain mature orderliness is evidence that he understands their necessary function for the health of the Body of Christ. 
The more critical question then would be, "If you indeed concede that the continuationist interpretation of these chapters is correct, how and why would you  justify disobedience to Paul's instructions here and try to persuade other believers to also disobey or disregard them?"