I wasn't aware the B-52 could do that so I checked and it can, 20 degrees left or right. Then checked to see how far a C-5 could turn and it was also 20 degrees.
But I found on
airlinersdotnet a discussion claiming The C-5A had this feature, the C-5B did not, then it was removed from all the C-5As. The reasons given were maintenance issues, complexity and improved landing techniques. Sounds like military bullshit to me.