my take on picking apart the rack and blasting it is this, its easy to look at a rack and see how you can pop 3 balls out here and then bump there and so on because you can easily see the outcome and reaction the balls are going to take. This gives you more control over your shot selection and ball placement.
By blasting the stack its harder to control the spread of balls and congestion of clear shot alleys, because its so hard to plan that whole spread. At the same time it leaves you many more options to play a good safe if the balls are not spread all over gods green glory.
Playing safe with a fully open spread can at times be a futile as playing safe on your last stripe/solid in 8 ball(when you should have played safe 2-3 or more balls before), all the balls are wide open and you aint got nothing good to hide behind....and I hate relying on leaving distance, there are some good shot makers out there.
lol i learned that the hard way.