I must of writen #2587 when I was half asleep. When I reread it the next day, I immediately realised my confusion. I was about to close it, but then it dawned on me: some people WANT the blf to function as intercom. Some people prefer the blf to work as call pick up.
Maybe the best would be to incorporate BOTH features, like this: when you press the blf, if the extension is ringing it will act as call pickup. If the extortions is available it will act as intercom. If the extension is busy, the call will go to vm, vmx, etc. (or perhaps it would function as "force overide" of paging?).
Obviously, all it would be possible to enable/disables all the options from the extension/device page for those that want the "classic" behaviour.
This kind of call routing would extended the capabilities of high end phones which aren't written specifically with asterisk in mind, yet (IMHO) should support such configurations (such as Polycom - which doesnt support call pick up (and the grandstream does - go figure!)).