I can kind of agree with your sentiment. We should run experiments, regardless of our skill level. We should, in fact, regard anything we do as an experiment. Very few decisions in the real world are irreversible. Doing experiments doesn't mean there's no skill to it. The Senior engineer will know what hypothesis is most likely to prove true, and will start with a system design that will work out well assuming that hypothesis to be true.
This is what the previous commenter referred to as "making a decision without all the evidence". If the senior engineer turns out to be right, and the hypothesis proves true, the experiment becomes the system. If the hypothesis turns out false, the system might still be workable, otherwise it's refactored into some new experiment.
The senior engineer is better at making that initial guess as the correctness of a hypothesis. Just like a senior scientist.
This is what the previous commenter referred to as "making a decision without all the evidence". If the senior engineer turns out to be right, and the hypothesis proves true, the experiment becomes the system. If the hypothesis turns out false, the system might still be workable, otherwise it's refactored into some new experiment.
The senior engineer is better at making that initial guess as the correctness of a hypothesis. Just like a senior scientist.