As someone with a role that includes Sales & Marketing (S & M :mg: ) - not to mention that the product is ISO 9001 and assessment & certification by a fantastic certification body

I feel the need to step in.
They should be conversant, but the need to converse about it won't come up much. They should know things they might be asked in passing, such as who the registrar is, how long the company's been registered, etc.
The only reason for ISO 9001 to come onto the salesperson's radar is if it gives a competitive edge. As has been mentioned if the market is saturated then it probably won't even come up. They may get asked about it and it would be handy for them to have some information to hand about what registration they have.
Perhaps you could put together a leaflet explaining how the company is registered, by who and for how long etc. Beware the marketers or work with them to make sure your leaflet is in the house style and do concentrate on the positives - Sales is an exercise in putting across the positive aspects of what you do.
You said (quite accurately) that sales people "are not like us..." Part of what makes them not like us is that they can incorporate fantasy into their sales strategies.
Now, you're not bitter are you, Jim. Not been missold anything recently?
If you tell them about limitations, or any sort of anything that might make a sale more difficult, their eyes glaze over and they have to be rebooted. The same applies more or less to dealing with reality, because they have their own, and it's not like ours.
As someone from the "other side" I can confirm there are a range of different grasps on reality - I obviously put myself on the "realist" end of the spectrum.
Perhaps there are others who bend the truth to suit the pitch but I can't possibly comment.
There is an element of change of attitude that covers could pick up on, though. IF we can emphasize some more of the positives then we, as a profession, won't be seen as the "guys and gals that say NO!"