code: protected boolean canSplitOnCapacity() {
          if(0 < _split) {
              // The splitTo must NOT overflow the current capacity
              int splitTo = _levelCapacity + _split;
              if (capacity() > splitTo && splitTo >= _levelCapacity) {
                  return true;
              }
          }
          
          return false;
      }
docs: Perform split on the current capacity.