Could you elaborate on those reasons?
Interesting you mention that. Over the last few days I've been dealing with a business served by a PBX (not Centrex). They have one listed number for all incoming calls. But when I get calls from that business, the caller-ID could be anything (though in the exchange for that town.) Indeed, in thinking about it, when I get calls from other firms with a PBX the same thing happens. The caller-ID is telling me what outward trunk line happened to be selected for that particular call.
[Moderator snip]Heck, say I was a small business with a simple key system, and my lines were 555-2300, 555-2301, 555-2302. I call out on -2302. Now someone could call me back on that, but the main number of my business is -2300.
In any event, it seems to me that if any substitution must be done, it should be done at the originating central office and nowhere else.
The idea of people hitting a button on their caller-id box to return a call seems very foolish to me. Just because someone calls from a particular phone does NOT mean they'll be at that particular phone when the call is returned. Someone could be at a pay phone or a stranger lending them a phone to use*. They could be leaving their office or home headed somewhere else. They could be at a friend's house.
- Now that pay phones are rare and calls are cheap, many businesses will let a stranger make a quick local call as a courtesy. Many people will lend their cell phone to stranger, say at a train station, to make a quick call. This sort of thing happens quite frequently.