He's not saying he thinks he's good enough, he's saying there is clearly something going on in that Lancaster and co rate him very very highly for a number of reasons and that he has the sterotypical rugby player physique - kind of like Lewsey in 1998/99, and that rating him is not on the basis of his reputation in league but a ton of immeasurables.
Ding ding ding we have a winner. I'm not sure what would have been unclear on that post.
I would also point out that any conversation about what they see in Burgess compared to his competitors is probably more realistic if we're talking about Burrell, Barritt et al.
However, to touch on a crucial point; I'm guessing what they want from all players this tournament is someone who they can trust to keep their head if they're on the field in the final in the 79th minute in a one point game. No amount of ability will make them pick a player they cannot trust in that scenario for whatever reason (although they've some funny ideas of who to trust) while a player who they trust implicitly can get away with a lot of sins. Big game experience, mental toughness and leadership abilities are clearly key to that. If Burgess did triumph over Itoje and Ewers for a slot in the squad, that is probably why. But he probably didn't.
Note - I am only guessing. But what I'm not guessing about is Lancaster and Farrell really liking Burgess for some reason. I can't help but feel it makes more sense to try and decipher what that reason is than it does to simply assume they're insane/incompetent for not agreeing with us.