Here's the thing about 6 packs... there is difference between having one and seeing one The only way to see your six pack is to be quite lean. As far as my training goes... it's nothing special, I believe that the majority of results people see or don't are based on diet! Here's my current training program... I do 5 sets of 5 reps on most excersises... my wife follows the same program but 3 sets of 20 reps for max fat burning and to improve definition...
mon+thurs chest/tris/shoulder
tue+fri back/bis/shrugs/deads
wed+sat legs
sun no weights just abs and cardio
I train abs 7 days a week... 3 sets of 50 leg raises with a medicine ball between my legs and 3 sets of 50 crunches with a medicine ball on my chest...
I do as much cardio as I can...
Since I lost all the weight, I have turned into mean lean fat burning machine... honestly, this is what I am eating in a day now... if I eat less, I end up losing more weight and feeling weak!