Scott Clark grudgingly admits that a Baptist can be a Calvinist, but he can't be "Reformed." And he can't be "Reformed" because Baptist theology is (allegedly) out of kilter with the 16-17 Reformed confessions, catechisms, &c., at key points.
Traditionally, Reformed theology, especially the Presbyterian variety, involves a hermeneutic of continuity, in contrast to Anabaptism, with its hermeneutic of discontinuity. And, of course, that’s what grounds the Presbyterian practice of infant baptism.
Other positions range somewhere within that continuum. The Baptist theology of the LBCF lays more emphasis on continuity, whereas NCT lays more emphasis on discontinuity.
However, the covenant theology of Kline, which underwrites 2k, and rewrites traditional covenant theology, involves a hermeneutic of discontinuity. It's the polar opposite of the WCF, and other suchlike.
Yet covenant theology is a central feature of traditional Reformed theology. And that differentiates 17C Presbyterianism (and its Dutch counterparts) from those "un-Reformed" 5-point Baptists.
So isn't Clark's core position pulling in diametrically opposite directions at this juncture?