Interestingly enough, if you are able to learn now, it does not appear to matter in which order the device button is pushed; before or after the 975.
In the steps you listed, you pushed 975 and got two blinks, THEN pushed the device button (RCVR/AMP) and the button you wanted to learn to.
In the steps edmund listed, he pushed the device button FIRST, THEN entered the 975 and got two blinks, then the button to learn to.
Unless you changed the order in which you were implementing the steps, it doesn't appear to matter.