In your article on Cold Steeping (ala Stong and Gruber) you state:
If you intend to add the extract to the boil pot, pour it in within the last 5-10 minutes of the boil. If you add it earlier, the length of the boil can bring out some of the harsh attributes. If adding to the fermenter, take care to avoid oxygenating the wort.
I don't understand this. We buy sintered stones and oxygen tanks to purposely oxygenate wort before pitching the yeast. Please clarify.