To answer the original question, I would say that a mild cam is one that works well with stock components. Vacuum devices operate properly, intake and exhaust manifolds are adequate, carb should need no, or minor, tweaking, rear end gear does not need to be changed, gas mileage does not change too much- and may get better, fairly smooth idle..... There may be more, but that pretty well covers it, I think.
Banjo
