the point im getting at is WHY someone can make the mistake, SUSPECTED head gasket on a car,,,,, considering how many cars he sees and when he prob done hes training,,,, with the limited info hes got on a laptop hes gonna summerise what he THINKS has caused it

but can see what might be the issue

that was the point, dealing with cars every day you forget just what every part is,,,,,, even if you know the answer you forget