Why doesn't BGP...

    "101 north is congested, take 280 instead"
Guess what hapens 5 minutes laster;
    "280 north is congested, take 101 instead"

Sort of like the cruise control in my car. The car starts going too
fast and it *eases* off. The car starts going too slow and it adds
a *little* more throttle.

My cruise control works quite well. So could routers.