I have read all i can on SFO flow control but cant seem to find out
why certain routes get all huge flow controls and others none.
For example last week all

MSP SFO on DL and UA 3 hr delays all day
while ORD SFO UA AA no delays

Is it a balance of FAA issuing the the flow control first
and then each airline figuring out what routes/flights get priority?

Thanks