Grace in Turretin's CoW

Dr. J. Mark Beach of Mid-America Reformed Seminary, in his PhD dissertation (undersigned by Dr. Richard A. Muller) presented to Calvin Theological Seminary, finds grace in Francis Turretin's conception of the Covenant of Works.

What now??!! LOL.

Christ and the Covenant: Francis Turretin's Federal Theology As a Defense of the Doctrine of Grace, pp. 86-90

Prelapsarian Grace in the CoW—A No Tread Zone?

Was there an element of grace in the CoW? If, as John Owen states, Adam had the Holy Spirit, was not this an indication of grace? Does this view constitute a "flattening of the COW and COG [that] will actually get you somewhere... where Christians should never tread"? What if divine grace was actually part of God's essential attributes? Should Christians really not go there?

Let's allow Dr. Richard A. Muller to provide some precision here: