All I want to say is, giving him the benefit of the doubt is fine...but I did the same with my H when it came to what he was doing...and he was lying to my face the entire time. Do all of them lie...no wouldn't generalize that way, but a great many people who view porn regularly do lie about the extent of their activity.
My H flat-out lied about what he was doing. He would say "it's not like I'm paying to be a member of a website"....he was and he knew it when he said it. He'd been on AFF for 2 years, paying for his membership the entire time. He would say "I'm just looking at pictures", he wasn't...he was actually in the "friends" list of people who had interactive webcams and would regularly receive e-mails from them about when they'd be online through his Yahoo account (these are people he found through AFF). He would say "I would never do that, that stuff is disgusting", yet he did it anyway and lied to my face about it.
If you H does have a porn addiction, it's unfortunately VERY likely there is much more that he is doing than he is admitting to. I know you probably don't want to hear that, but it's VERY likely...with someone like this, it's the nature of the best so to speak.