NYT links are all paywalled for me, but I can't envision any possible excuse for what he did. I understand that "access" is a tricky problem and involves some moral grey area, but sending articles ahead of time for revision and "vetoing", and asking for permission to use a quote... those both strike me as a clear failure in journalistic ethics.
So should journalists simply never agree to have conversations off the record?
I think there are big problems with the way access and coverage are mixed up together and traded on, but I'm pretty comfortable with a journalist agreeing not to publish remarks made during a conversation and then later asking to publish some of them.
"Here is the quote that Leibovich is intending to use from your conversation with him unless we see a problem. I don’t."
https://wikileaks.org/podesta-emails/emailid/33945