Oh I certainly count him among the favourites, no question there, based on the history you mentioned. My point is that we can't just say that it will be impossible to beat the Slovenians outside of ambushing them because they are just stronger. Of course they are favourites but people talk about them as if they've already finished 1-2. Just look at Bernal at the Giro. He might have seemed unbeatable and people didn't really consider trying anymore, but then when it turned out that he wasn't completely invulnerable, it was too late. With this view you've already lost before you start the race.Of course we can say that Slovenians are two biggest favourites and we have every right to assume they're probably the strongest. That's because we base our assumptions on longer period of time than just these last two months, when we indeed haven't had a chance to see them in action.
Roglic was in a great shape during the spring races, the route suits him very well, we can see he's constantly progressing from one season to another both physically and tactically. He's chosen not to race for these 2 months purposely, not because of any injuries or other wekanesses. His team decided that preparing in a controlled envinronment of training camps will be beneficial for him, to show at his best in the Tour.
And personally I don't need any extra validation in a form of good performances in TdS or Dauphine. He's already an established GT contender with 2 GTs in his palmares, who almost won last year's Tour. Obviously, we can't make any claims with 100% certainty that he's faster than x or y rider. But this applies to any other rider and the fact that one beat another in Dauphine doesn't mean the same will happen in the Tour. Putting Roglic only as a 4th or 5th favourite (just like CN did) just due to his absence in recent races (not caused by injuries) is kinda naive for me.