Cut nails do sever the grain nicely as they punch their way through the wood, and are much less likely to split the wood, far superior to wire nails IMO.
It is however, a little recognized aspect of the diamond point on wire nails that there is a direction to place them. The diamond is asymmetrical and there are cut edges, they are though less recognizable than they were in years past and not as sharp, and not recognizable without a visual inspection necessarily longer than most would give them even if they knew they were there.
I thought the term butt cog was in more common usage than it apparently is. It is essentially the end of a drop in joist or purlin fully housed width wise though often the drop in is reduced in height with a relief cut.
