Maybe binding/off angle

I remember quite a while ago there was a problem with the heavy-duty (L88 type) BB Chebbie rods, they came with a super hard bolt (I think they were referred to as the "boron" bolts)and there was a lot of breakage. One of the major builders torqued one up one day, sat it on the bench, and started working on something else- about 10 minutes later the head of the bolt fell off. Seems the machined seat for the bolt head had distorted a minute amount, probably during the bolt replacement, and put the bolt in a very slight bind- but the bolt was too hard to bend/conform, and fractured from the stress- sitting still. Maybe those adjusters are a little too hard to work with the side loads as the rockers cycle through their action?