If you read Dr C Cone's reply in it's entireity, there's a quite clear message about re-using dried yeast. He went on to say:
"However, we feel that it is prudent practice to limit the repitching to two or three times at most. Even the big breweries, with all of their sanitary savvy, limit their repitching to less than 6 times The cost of dry beer yeast is such that it is economical to maintain minimum repitching practice. Many brew pubs do not attempt to recover yeast for repitching, they just rehydrate and pitch fresh each time."
Repitch 2 to 3 times AT MOST. Many brew pubs just rehydrate and pitch fresh each time. If I was reading between the lines, my guess is Dr C Cone is saying, yes our product has improved, but don't bother repitching becuase dried yeast is cheap and specifically designed for simple one time applications. The tone of his comments suggests that even with liquid yeast, you should limit the number of times you repitch, because as home brewers we are just not equiped to keep a culture pure.
"Good laboratory and sanitary practices are equally important. You would be surprised how many single yeast colonies contain bacteria when you streak from an infected wort."