In the "Final" version of the 2017 Rules, the Code of Official's Signals is now Appendix E, and the Summary of Penalties has re-appeared as Appendix F.
I was just about to ask everyone about when to use S38 in conjunction with other signals for personal fouls. Many moons ago, it was used with just about every personal foul, but I knew that had changed back in the mid 2000s, I think. I just happened to check the "Final" 2017 edition of the book and discovered these "updates." The Summary of penalties shows when to use S38 with other signals.
Curiously, it says to use it with roughing the kicker, but not with roughing the passer. Seems odd, but, OK.
Robert