Apparently then whoever added that tidbit to your filter isn't on the same page as the rest of Volvos literature because I even double checked this in VEN and Vadis.

There's no good reason why you or anyone should do what THOSE instructions then say.

In Vadis, with your car ('00 S/V 70s) the ONLY programing for ECC that has anything to do with the pollin filter is that one can either remove or add ANY pollin filter to its programing and all that that does is increase or decrease blower motor speed depending, nothing more. For example, your car comes with that filter (no not carbon but....) so if you wanted to remove it completely and be without one, the blower motor will blow slightly faster than normal and thus be a tad noisier. Once the 'remove' programing is done to that car (with filter removed permanently from car), the blower motor will blow at a slower and more normal speed.

Our dealer has never installed one of those filters, don't stock them and no one's ever asked so you're right in that I've not seen THOSE instructions that you have.

I'm not here to argue with people but my whole point really is that IMHO, I wouldn't waste my time going to a dealer and paying them for an un-necessary service.

Add that filter to your car and see if you notice anything different. I highly doubt that you will.