You have to look at it in the context of this team, this year. Not just a generic overall view of what those practices might be to any team.
The team is learning entirely new systems on both sides of the ball. To think they are completely installed at this point is foolish. The players are still learning, and will still be learning in December. It's not like Alabama or FSU where the seniors have been getting reps in this system for 4-5 years.
Dino himself has said it would take 18 months to get everyone on the same page with the fully installed system. How in the world could 15 additional practices not help get us ahead of schedule?
Even if you were right and the practices are "walk throughs" (I disagree but that's beside the point), they will still teach the players to make the right reads, and make them faster. That's what's missing right now for some of them, and I suspect that will still be the case in December.