You must be a coach, because you took what I said, recycled it, put your own spin on it so it looks like you invented something(smart mileage), and in the end, really just muddied the waters.
The mileage debate has been over for years. All elites do the same things. Do you see any elite marathoners doing 30mpw and just intervals? No. Do you see any elite marathoners doing just tons of easy miles and no work-outs? No. Do you see any elite 5K guys who do no intervals? No. Yeah you may get someone way off on the bell curve who bucks the trends a bit, but the exception does not make the rule.
Running is fundamentally an aerobic activity. All running trains the aerobic system. Therefore more running is better - unless you start not absorbing those miles. If your musculoskeletal system can't handle it, you get injured. If your endocrine system can't handle it, you get overtrained. But there is a very, very consistent correlation between how much you run and your race times. Jamin's right, that the studies exclude people who got injured because they don't end up as a data point on the miles ran vs race time graph. But it doesn't change the fact that more miles is still better for performance.