[sunyc]

it is under used because most of the time, you just don't have to care. and when it matters it lack the depth you need, like layer 7 detection.

it is almost always better to just pay for bigger pipes.

[rbanffy]

Wouldn't layer 7 detection drive CPU usage up for a somewhat different use case? You are not trying to give video traffic a lower priority - you are trying to prevent things like backups clogging your pipes.