Well, fully, what it does is: (A) spiritualize unfulfilled prophecies of blessing and take them for the Jew/Gentile Christian Church; but (B) leave the cursings all as literal, and all as applying to ethnic Israel only.
Neat, huh?
It is, I say seriously, the sort of "interpretation" we used to do in the New Age cult of Religious Science -- except, thankfully, they almost only do it on prophetic and Israel-related passages. When it comes to soteriological, theological passages, Reformed exegetes are as good as it gets.
Well, better to be right on the major issues and wrong on minor ones, than to be majoring on the puzzlement regarding the secular state of Israel and prophecy and allowing wacky theology and soteriology. (Not that reformed folk are wrong on eschatology. We just aren't drinking Scofield's kool aid and seeing the same thing.)