Didn't people say similar things about Tech when Paul Johnson went there? They have done quite well on offense considering the marginal, at best, talent they get.
2 things. First, Paul Johnson had some stud Chain Gailey recruits his first year (Demariyus Thomas, Jonathan Dwyer, Josh Nesbitt, etc). He inherited a perfect scenario to run that offense.
And as for your last sentence, what happened at tech is exactly what's gonna happen at duke. The first year, MAYBE 2, duke will actually have some success due to a)people being totally unfamiliar with scheming against it and only being able to devote 1 week to do so and b)the players they currently have will probably be servicable.
The major problems with duke, just like at tech, are gonna really show through after about 2 years. High school kids don't want to play for an offense like that. No WR is gonna go because they just block all the time, most good QBs won't go because they'll never get to throw, many OL won't go because all they do is run block every down. And most good defenders won't go because they'll just play against that crap all day everyday in practice.
I think it's a neat idea and will probably turn some heads and raise some eyebrows in year 1 and 2. But then they're gonna really be in trouble.