He was just pointing out the obvious; one of the design constraints already well understood with environmental limits defined by the engineers at Thiokol (and in this case over-ridden by NASA management)

I know a couple of the people on that investigation personally. The thermo case of the o-ring was already well known and any "pique" is internet history now, witness Wikipedia authors laying it all on Morton Thiokol's O-ring itself.

The probable cause of the O-ring failure was not only NASA management over-riding Thiokol's call to scrub because the ambient thermal conditions were not met, but deformation of the ring itself caused by the shipping and transport practices of the components.

The second component was evidenced by the conditions of several fasteners between rings and between ring and skirt trying to "force" the shapes back into round at the sealing surfaces.

The combination led to the O-ring arguably not being captured properly or being deformed during assembly, as well as being used outside the condition limits (already understood and established with practices in place). It was a one-two punch.

Acceptable deformation was reduced and a new capture system that went around the complete periphery of the sealing surfaces were the solutions.