I used to travel a lot for work. In many of the cities/towns that I was traveling too, there were usually very limited options. And in a lot of cases, I really didn't have time to scout and find a good restaurant and would simply go to a familiar chain. What I found was that Outback was really different from town to town and usually not very good. Longhorn and Texas Roadhouse were pretty consistent so that I stood a good chance of getting something that I liked.
But as usual, if I had the time to talk with the locals and scout around, the small mom and pop place, always was a better option. And I found some pretty good ones over the years.
As for Carrabba's, I had never eaten at one until one day when I had about a 2 hour layover at O'Hare in Chicago. There was a Carrabba's in one of the terminals and I ordered the Fettuccine and it was very good, (or I was very hungry). I then ate at one in Charleston SC, and it was subpar. So it really does seem that even though you are at a chain were you would expect that there was some consistency, it really is hit or miss.