Little secret about +Sanborn is that he only signed on with CT because +McKenna insisted that he would not consecrate a straight sedevacantist but only someone who held CT. So ever since then +Sanborn has adopted CT, somewhat grudgingly, with a sedevacantist spin to it, minimizing the implications of the material papacy. But by minimizing these implications, +Sanborn also causes the theological benefits of CT over sedevacantism to evaporate.
In this particular answer, likening material pope to a mere pope-elect, he involves himself in contradiction. If these popes are merely pope-elect in the true sense, then Ratzinger (was) NOT a pope-elect himself. Why? Because a pope-elect cannot appoint Cardinals. So the Cardinals who elected Ratzinger (mostly appointed by Wojtyla and some by Montini, also themselves mere pope-elects) could not have legitimately elected Ratzinger to make HIM a pope elect. That's where +Sanborn trips himself up in this particular answer. No, the implications of CT is that these men become MATERIAL popes and then can do things like make appointments and designations from a legal standpoint ... e.g. appoint Cardinals who can then in turn elect other popes. This is also the part of CT which evades the problem of ecclesiavacantism because a legally-designated material pope can make appointments to episcopal sees, and the bishops appointed, if they themselves do not labor under any impediments to prevent them, can formally exercise office. But perhaps he was using the term "Pope Elect" as a shorthand way to dumb down the notion of "material pope".