I can't tell for sure, but the Titan j-hooks look to have a raised weld on the inside vertical wall.
Is this the problem you are referring to?
I bought some NY Barbell j-hooks a while back to replace the awful hooks in my cheap rack. The new ones have the same issue as the Titans. I have black j-hook. They look similar to these.
http://www.newyorkbarbells.com/9257.html
And the weld on the side piece sits out a little too far.
This damages the knurling on my bars. I put 2 layers of heavy duty velcro over the inside cup. It seems to work for now. I've considered gluing some uhmv in there. . . . The uhmv lined Rogue hooks look far, far better.
I also put some pvc over my metal safety pins. The bar is much happier now.