First, (§3.1) we might say that there isn’t any requirement of reason to be instrumentally coherent as such, but whenever one is instrumentally incoherent, one violates some independent requirement of reason.  Second, (§3.2) we might say that there is a requirement of reason to be instrumentally coherent as such.  Third, (§3.3) we might deny that one necessarily violates a requirement of reason in being instrumentally incoherent; perhaps the normativity of instrumental coherence is merely apparent, or the requirement merely evaluative (it may be a standard of proper functioning without giving anyone reason to comply with it).  Fourth, (§3.4) one might think, given the ways in which intention is thought to involve belief, that in being instrumentally incoherent, one violates a requirement of theoretical rationality. 