I have been doing SGHP before Deads, just wanted to get feedback from folks (like you) with more experience as to whether or not there was a reason I shouldn't (ie something that I'm not aware of). I'm new to 5/3/1.
For me, with the SGHP, I stop as soon as my form gets sloppy. I can just start to feel that while the bar may have gone up, it wasn't "crisp" for lack of a better word. I say 3 x 6 in my programme above, but really I mean when I get to 3 x 6 I then increment weight. Most of the time I'm in the 4 or 5 range.
I used to have some shoulder issues from too many chins. I have since recovered. My chins are mostly neutral grip, though I do vary it some times. I just try to be gentle with them as I don't want any recurring issues. I read about SGHP from an article by Christian Thibaudeau and thought I'd try them (this was a while ago). I really enjoy doing them. That is the only reason I do them.