Barber Chair on a big Oak

This big oak begins to fracture vertically and is about to Barber chair when I chase in the cut and keep it together.

I knew it might try to barber but I saw a little dark spot in the center when cutting the notch so I knew there might be some brown rot inside and because of that I opted to not do a bore cut and just chase it in if it starts. Was glad I did, turned out to be hollowed out inside with a ton of brown rot. If I'd bored it I might have lost the tree. But this way I was able to steer it over and keep the trunk together.