Notably, Codeblock doesn't say that it can't be applied to hacking actions "a decker" isn't likely to take. It says Characters can't apply to actions they are never likely to take. So unless you can honestly tell a GM, oh yeah I set Data Bombs all the time, you probably shouldn't be trying to apply it. It's like a Magician techno-phobe taking Incompetent (Engineering). If the decker took the Code of Honor: Like a Boss negative as well as Codeblock (Set Data Bomb), I'd be cool with it... but that's because Like a Boss basically forces the decker to only use Data Bombs as a method to deal Matrix Damage.
And yeah, in a recent update to the Missions FAQ, they allowed Code of Honor for specific codes. Basically, the individual codes are marked as "not ok" and making up your own code isn't allowed. Just Assassin's Creed, and the ones from the other splat books that aren't on the banned list, most of them are in Run Faster (because they put a huge list of codes in there). Also, they altered the penalty for breaking your Code so that if you break your Code more than once a mission you take considerably worse and worse penalties. Second infraction burns a point of Edge (not spend, burn), then you lose the ability to spend edge, then you lose all karma earns for the mission (in addition to that first infraction losing a point off your current earned karma).
EDIT: Speaking of Incompetent, Incompetent (Firearms) for a close-quarters guy would be interesting. I've lost count of the number of times that a Melee specialist has basically been put out of combat because they couldn't close the distance, so not being able to pick up a gun would definitely fall under the line of "it still affects them."
