If you remember watching the movie....he took a pexiglass pen and drew every line and possible approch that the barrells, springs everything...There was even some way that he would move mario and doing it would make the barrels either go or not go down ladders....
Donkey Kong is a fun game...but it BLOWS my mind how a man can break it down to 10001110101 (binary)...
Those things arent that difficult, I can help you with them.
The first one, the springs have several flight patterns, the important one is the one which bounces the furthest in to DK's foot. If you sit and watch the springs, just watch where they hit on DK's foot, you will see there is one that is the longest.
When that spring hits, Steve starts to run Mario toward the ladder, but keeps his focus on the springs. If another long one comes as the next spring, you have to run back, it will hit you on the ladder. Thats why you will see him start to run, then go back, sometimes several times, until he goes. Hes waiting for the random pattern of a long spring, followed by a short one.
As to barrel control, how it works (past level 1), is that if you are pushing Left or Right on the stick, ALL barrels above you will go down the next ladder they hit that is that direction. It doesnt work on every barrel every time, but it usually will work. This way you can force barrels to go down ladders that wont hurt you, and you can time barrels to give you better jumping/smashing patterns.
You can also push left or right when on ladders, or mid jump to control the barrels as well.
Getting the control takes practice, but doing it as well as Steve does is masterful.