Personally, I'd rather have a cold set in stone time frame because it allows you to plan. What is "prompt"? I would say anything inside of 2 hours from call to show would be darn good, but I don't really know what they want by that.
The Airways 90 mins normal driving time to the airport lot was actually pretty decent for their bases. I understand with AA it wouldn't be ideal, one could make it 2 hours or something normal driving time for specific bases. Keep in mind it wasn't a 90 min call out, just that you had to be within that 90 min ring around the airport.
None of the reserve language I've operated under specified to "push", it was always a call out to be on airport property. You of course have to check in, read mail, update your iPad, look at weather, etc. etc.
I would think *most* people on property are professional about it and aren't laying tile getting a quick call and finish the job, 3 hours later they head to the airport, etc. However that is why there is a CP.
Saying it will only effect a small amount of the pilot group is a ridiculous argument. So does the 190 and look how everyone feels about that. Hell the company can't even staff it.