I'm looking at the SI book for this one... not interested in going to Mahwah, though..
So far, as I can see, there was a man who claimed that he was on his way to Heaven, but Paul could not confirm this was true, since he didn't experience it. This would have occured circa 41 CE. Paul said he knew the man, but did not identify him.
It appears he was suggesting that everyone take him at pretty much "face value"-- that he doesn't appear to be more that what he is... This is brought out in verses 6 and 7(a) "... For if I ever do want to boast, I shall not be unreasonable, for I shall say the truth. But I abstain, in order that no one should put to my credit more than what he sees I am or he hears from me, 7 just because of the excess of the revelations. Therefore, that I might not feel overly exalted..."
It could be this man was trying to draw attention to himself, exalting himself based on this "experience". Even though Paul had more confirmed, legitimate inspired visions, he downplayed those (unless when making a point) and let his visible actions (ministry, imprisionment, etc) speak for themselves.
That's what I get out of it... I could be off the mark...
focus more on the third heaven, my friend.
Well, I know it isn't the fourth away from seventh Heaven... going on a study, then I'll be back