He had reached a critical point in the ratio of strength to body weight, one that he had now surpassed. Lifting a 35-pound item with 50 pounds of force versus 60 pounds of force is not simply an additive effect.
He had secretly tested it and his strength had reached a level where he could hang from the horizontal bar and rest. If he increased his grip strength, then his power could no longer be described as simply a matter of how many horizontal bars' worth of force he had.
However, it still wasn't enough. Relative strength was only good enough for him to control his own body and perform some exaggerated movements. Real rescue often involved combat with heavy objects, with the heavy bodies of unconscious victims, and even operating cumbersome equipment requires absolute power.
