What the author calls technicalities, I call the essence of the Gospel. In Christianity God becomes man to be a propitiation; Mormons think that men become Gods. Joseph Smith was a false prophet with a fake gospel;
Galatians 1:6-9 I marvel that you are turning away so soon from Him who called you in the grace of Christ, to a different gospel, which is not another; but there are some who trouble you and want to pervert the gospel of Christ. But even if we, or an angel from heaven, preach any other gospel to you than what we have preached to you, let him be accursed. As we have said before, so now I say again, if anyone preaches any other gospel to you than what you have received, let him be accursed.
Bingo! (To use a late-Saturday night commonly heard term)
To Mormons like Joanna Brooks, she fails to mention the "Grand Canyons" & as you said, focuses on so-called "technicalities." One of those "Grand Canyons" are that in true Christianity, men don't join the ranks of godhood to the tune of billions...like Lds "apostle" Orson Pratt taught. [Orson Pratt was the brother of Mitt Romney's original Mormon ancestor]
Another is that Christianity reveres, respects, worships, honors, glorifies and fears the Ultimate God who has always been God. Mormonism doesn't. In fact, Mormonism militates vs. such a God by trying to pretend that the average man or woman is as eternal as God is.
[See Lds Doctrine & Covenants 93:29,33...which teaches that before any "spirit" baby was born near Kolob to a mom-god and a daddy-god, everybody...including all the gods...were "hangin' out" as intelligences in goo soup somewhere]