Should the church Proscribe against Promiscuity

This comment on my post on the church and sex has caused me to think....

On that basis sex should be treated just as any other human interaction, with the main moral proscription being that we shouldn't harm others. So, I don't see what business it is of the church's what people do, as long as they aren't harming anyone. There's no good reason for proscribing against promiscuity, except to the extent that it is performed without regard to the wellbeing of any partners involved. 

The author of it of course knows well that I am doubtful that promiscuity can ever be a good thing. So should I (as a representative of the church) proscribe against promiscuity?

I believe that the church advocates and proscribes against certain behaviours:

Advocates
1. Prayer
2. Worship
3. Loving others as ourselves
4. Kindness, patience etc (Fruits of the Spirit)
5. Obedience to the law, if it is just
6. Relationships that are harmonious
7. Sex as part of a loving relationship

Proscribes
1. Injustice
2. Selfishness
3. Hatred
4. Pride
5. Abuse
6. General going round killing folks..

The truth is that some of my friends are promiscuous and I don't mind. I work on the basis that if it doesn't hurt anyone then it is none of my business. However, I don't actually think promiscuity is a good thing, and I think it is reasonable to expect ministers to be monogamous. So should the church proscribe against promiscuity? I think it should advocate monogamy but not condemn promiscuity. I think that is okay, in the same way that we advocate prayer but do not condemn those who choose not to pray.