I'll try to get some computer time today and markup a picture with some ideas for the taper and geometry towards the connector end and send it to the list.
By the way, the Analog Devices employee's recommendations can't be exactly normative with my understanding of transmission line impedances--differential impedance < 2 * single-ended impedance. (In other words you'll want single-ended > 50Ω if you hope to get differential = 100Ω.)
I'd consider them design guidelines or goals in order to try and keep the process from going in the ditch.