The long bitter butter battle over OOXML should have ended with the ratification from ISO. Instead, those who cannot accept that decision decided to go to the streets. I respect Steve Pepper, but this time, he is wrong. I respect Tim Bray, but he is very wrong. Bob Sutor is an IBM VP of Standards. He is working for a corporation on a suicide mission. He has my sympathy, but between the anti-Microsoft tactics and now the push to move all IBM employees to Macs, thus killing off IBM's most profitable business units, IBM is moving beyond wrong into dumb.
Don't engage the anti-OOXML forces with explanations. Their tactic now is to accuse ISO of corruption, thus making it even more difficult to create international standards by negotiated consensus. They are moving on to a scorched Earth strategy that will ultimately destroy any real chance at maintaining open standards organizations if they succeed.
These are not reasonable people. They were full of fury before the vote, and frustration will drive them to be even more furious. You won't win them over with logical arguments or appeals for professional behavior.
The answer is simple:
"You lost. Get over it."