Mayo has an e-mail from Paul Lindsay of the McCain camp in PA:
McCain became a POW in 1967. The legendary Steelers defensive line that McCain appears to be referring to -- The Steel Curtain -- wasn't in place until 1971. Mean Joe Greene --the first of the front four to arrive -- didn't join the Steelers until 1969, two years after the time McCain refers to as when he was first interrogated.
In 1967, John McCain was 31 years old and the Steelers were anything but super. They'd had only eight seasons since McCain was born in which team wins outnumbered losses. In the two years before McCain was shot down, the Steelers were 2-and-12 and 5-8-and-1. Discouraged fans back then called them SOS -- the "Same Old Steelers".
I can't imagine it was a mistake. If you watch Delano's interview, it's all very carefully planned out. The pander enters the discussion immediately after Delano asks McCain what's the first thing he thinks of when he thinks of Pittsburgh.
On background as a McCain official - It was an honest mistake. If bloggers want to make fun of him because he forgot which team he used under torture, let them.
Hope that is helpful to you,
On the one hand, it's a teeny-tiny story. On the other, it shows Senator John McCain as willing to say anything even lie about his POW experience in order to garner votes in Pennsylvania.