The CHT is actually the most important engine instrument.
It is a direct reflection of the temperatures of the exhaust valves. At the highest CHT the exhaust valves will be at their hottest, not at the highest EGT however strange this may seem.
Advantage of the EGT is that it reacts in seconds, not minutes.
It is a pity most aircraft are not equipped with proper multi-cylinder instruments and properly trained pilots, .
Keeping CHTs below 400°F will go a long way to TBO.