Well after reviewing the fifth generation legacy tunes (stock and cobb), I noticed there is still timing being added to cylinder #4. Although the idea may be to concentrate knock to that cylinder, I do not believe it to be beneficial. Perhaps less than a degree may accomplish that, yet the tunes are adding over 2 degrees in some areas.
When I raised this issue in older legacy's, Cobb concluded that running negative timing in Cylinder 1 & 4 (dog leg cylinders) was the best solution.
All TA maps have this fix
and I'm guessing that if you contact Cobb, they will revise there maps. Just like they did in revision 118
Also there is some additional timing in cylinders 2 & 4 on various newer WRX's and STi's.
Beware. Another great reason to run TA maps, we stay on top of these things.