however many are reminded to do that by the 900ft wailer the boeing has built in anyway.
You would be dismayed if you saw the significant number of pilots who rely totally on the wailer to initiate their call rather than watch the altimeter. The wailer was designed as a back-up to a call that should already have taken place. We ran a series of tests in the simulator where the wailer was silenced and in almost every case crews failed to call the 1000 ft to go. I recall one pilot on hearing the wailer sound he automatically called "1000 to go" when in fact it was because the wailer was warning of a 300 ft altitude deviation from programmed altitude. A case of monkey see - monkey do..