CRM 2013 Duplicate Detection

Hello,

I read a post that in CRM 2011 any change to the entity's metadata will result in the duplicate detection rules for that entity being unpublished.

I have two questions - can anyone confirm that it is the same for 2013?

If so, is there any way to stop this behaviour?

Also, does anyone know if, -  when duplicate detection is invoked via code (reqUpdate["SuppressDuplicateDetection"] = false;) is there any way of specifying which specificduplicate detection rule to invoke (we have several for contact depending on the requirement) - or is it "all or nothing"?

I think that is 3 questions.

Any help gratefully received - thanks,