All engineering needs feedback to guide implementation, especially in complex systems. And it's essential in black box systems like biological organisms. This is why the words engineering and medicine intersect mostly in relatively uncomplicated areas like prosthetics or eyeglasses. In immune systems, engineering is used only in the earliest stages, like to reduce search spaces in development of synthetic antigens and antibodies for vaccines, never to guide clinical trials. There feedback drives all decisionmaking under the purview of statisticians only. Engineering, and especially intuition, plays no role al all.
Science is important, but there are times like this where brute intuitive engineering is the only tool available.