Thats basically an elite PL total, and those rep numbers don't add up lol. Nobody with a 600lb deadlift would only be using 155lbs for 12 reps
PL? What does that stand for? And the 155 for 12 is for the straight leg deadlift. It encorporates different leg muscles than the regular deadlift.
For my regular core workouts I alternate between two charts, a power chart and a endurance chart. As you would guess, each chart contains a different workout for your max (the chart ranges from 100-600 pounds) and each chart focuses on either power or endurance. The power chart for my deadlift looks like this
300lbs 6 times
400lbs 8 times
450lbs 2 times
400lbs 6 times
350lbs 8 times
And then upon completion of that section of the chart you move to the next max. It is a very good workout for your core because it allows you to focus on building your endurance and power and it has signifficantly incresed how much weight I can push around.