I guess technically you could be established for a straight in at 50 mls out or beyond only giving calls as necessary. The word "should" & "recomended" in the regs means to me anyway that it's not B&W & as others have said it depends on a lot of variables. I hear some regionals give 5 ml calls as established as "'cap'n"' said, they have done so for many years prior to ctafs straight ins.
FG