OEM Rocker Arm Side Play

I think I have read that in a really old DC catalog. I’ll look later today and see if I can find it because I’m pretty sure I’ve read the same thing 12many has.
Could well be.....and it could be my stupid *** is remembering it wrong. I have the Ninth edition engine book, but I caint physically get to it right this minute. It makes sense though that the pushrod cup would be one area of improvement. I have seen several failures there through the years.