Can anyone explain how a loose LCA would only affect hard pulls? It seems like that should have been noticeable during any acceleration or braking... I can't help but think there were multiple things going on and the LCA just brought it to the surface.

 

That's all it was for me and for a guy on the FB SC group with the same issue.
The bolt held it in place slightly. Under load, it moved. It was obvious that it was fixed in the first few pulls.