Goto the theory of control systems 
This is a textbook case of a system with too strong negative
feedback loop.
There are two ways to deal with that -- reduce the feedback
(say, make the announcement in a barely intelligible speech,
so only 1/3rd of drivers will get it :), or increase inertia
of the system (by posting 10MPH speed limit :), so announcements
can come fast enough to compensate each other.
Seriously, the load-sensitive traffic management _can_ be done,
but to do it you a) need full knowledge of the load patterns,
plus some historical data, and b) have a way to control system
in steps less drastic than rerouting an entire flow.
Can't be done with ciscos, or any existing routers...
--vadim
Is this really a discussion for this list-server?
I don't know about all of you, but I don't have the time to
continually read a re-hash of age-old discussion.
On the radio1::
"101 north is congested, take 280 instead"
Guess what hapens 5 minutes laster;
On the radio2::
"280 north is congested, take 101 instead"
goto on the radio1
Goto the theory of control systems 
This is a textbook case of a system with too strong negative
feedback loop.
There are two ways to deal with that -- reduce the feedback
(say, make the announcement in a barely intelligible speech,
so only 1/3rd of drivers will get it :), or increase inertia
of the system (by posting 10MPH speed limit :), so announcements
can come fast enough to compensate each other.
Seriously, the load-sensitive traffic management _can_ be done,
but to do it you a) need full knowledge of the load patterns,
plus some historical data, and b) have a way to control system
in steps less drastic than rerouting an entire flow.
Can't be done with ciscos, or any existing routers...
--vadim
Vadim, are you shure about this?
Withouth the friction - what would you got this case? Very big pendulum,
isn't it?
There are two ways to deal with that -- reduce the feedback
(say, make the announcement in a barely intelligible speech,
so only 1/3rd of drivers will get it :), or increase inertia
^^^^^^^^^^^^^^^^
of the system (by posting 10MPH speed limit :), so announcements
can come fast enough to compensate each other.
Seriously, the load-sensitive traffic management _can_ be done,
Exactly it's done in the lot of different systems.
but to do it you a) need full knowledge of the load patterns,
plus some historical data, and b) have a way to control system
in steps less drastic than rerouting an entire flow.
Can't be done with ciscos, or any existing routers...
I am not shure about EGRP, through.