I certainly have fallen into Skills A traps. It is tempting for those of us who like multiple role characters (and technomancers, who may have lots of skills and skill groups to cover). I have found that it is the skill groups that make it most difficult. Having too many skill group points leads to characters who can't specialize at character generation in important actions for their roles, or dump skill groups in places they don't really need for dice pools that aren't worth it when suffering from deficits in other parts of the character.
However, I really liked how this technomancer face turned out with skills A:
http://forums.shadowruntabletop.com/index.php?topic=21580.msg391140#msg391140With Skills B, this character could be a more specialized face, but going A allows it to be a potent and broad face while being a mediocre hacker too. (In retrospect, I would focus on crack sprites and drop intimidation for either a weapon backup or perception.)
So I know it's been hammered out here already, but when making a character and tempted to take Skills A, it is probably best practice to check yourself and think about what are you trying to cram in to the character that it could get by without and try with lower Skill priority first and compensating with special powers, gear, or edge.
I would like to think through what kinds of limited character builds where Skills A is most useful, though I don't know if there are any generalizations to make about it. Are there skill groups where individual skills are less essential for specializations or high ranks? I am thinking athletics and outdoors? Maybe stealth and electronics? Are there character concepts where having a broad base of these skills covered with groups and still have skill needs that require lots of skills and specialized skills? Does the character have lots of Agility, Charisma, and/or Logic linked skill needs with the attribute allocation to back them up?