I won't be disappointed or upset if the Tide gives up 24 or 10 (of course that comes with the assumption Bama comes away with a W.)
Consider: The two best teams Bama has faced in the season opener are WVU and VT. The defense gave up 23 and 24 respectively. Both teams presented different attacks from their QB just like both teams likely had a better QB at the time of the game. (I have no doubt Clint Trickett had a game Slave won't duplicate.)
Two teams have been held to 10 points: Clemson and VT again. If we look at the average we're talking about a bit over 16 points allowed.
We'll have mistakes. If history is an indicator one will be on special teams in coverage on kicks. The defense has always given up one or two big-plays (no matter how good the defense has been.) It's just a trait of playing man on the corners.
Bottom line with me: Considering it's the first game, against an opponent with a new coach and a new system, and outside of Pitt the staff doesn't really know what kind of game Wisky is going to call...seeing three TD's given up isn't a stretch of the imagination.