Agreed Dropline.
Also consider that sometimes no one has any idea about what the delay length is going to be. Also in some situations, due to their very nature, they snowball. Imagine:
- Plane X is due to fly MAN-LHR-MAN at (dep times 1200 & 1345 respectively) but goes tech.
- Plane Y, due in from another service is subbed onto the sector, but it will operate 30mins late. Both sets of pax informed 30min delay (after info has been telexed to LHR and relayed to pax service staff etc.)
- Plane Y is boarded and ready to operate the 30min late MAN-LHR service.
- No tug is available due to a/c being out of schedule - further 15min delay.
- Tug delay means missed ATC slot - further 30mins sat on tarmac before pushing and departing.
- A/c holds over LHR due heavy traffic - +10mins. (a/c now running 1hr 25mins late)
- Stand is not available due to a/c being out of sequence - +5mins
etc etc etc.
An airline operation is a very fluid thing. It doesn't take much to throw the whole thing out of kilter, and things change very quickly. I agree the situation described above is a crew's worst nightmare, but its not inconceivable (I've certainly seen it before). There is very little anyone on the ground can do to keep updating pax in the departure lounge in this situation. As mentioned above computer systems only give a basic delay reason to the pax service staff, which doesn't update until someone in ops has a chance to do so. Also giving pax the new ETD every time an update is received isn't always beneficial, it tends to drive people even more mad. Therefore we use our experience and give a best guess to the total delay, and only change screens/make announcements if there's a major change.
So although the 'delay will be approximately 1 hour 30mins' or 'further information in 30mins or sooner' announcements are infuriating to pax, they are sometimes the only sensible option.
Kudos to the BE FO who took your phone number, you wouldn't find many crew doing that. As ground staff I would not ring individual pax unless in exceptional circumstances - when delays hit we're extremely busy and would most likely forget anyway.
Pax service agents really aren't there to screw you over, we do our best under difficult circumstances. And as much as the lovely traveling public delight in shouting and ranting at us sometimes, we want to get you away ASAP, with the minimum of fuss.