I have powerlines that should be symbolized as ---P---P--- no matter how the layout data frame is rotated. The “P” should always stay perpendicular with the powerline. Right now, the only way to fix this problem is to check “Rotate marker symbols with dataframe” in Advanced ArcMap settings. The problem is this affects other features in my map that I don’t want rotated (and don’t care to set rotation angles to every one of these). I checked with ESRI and the problem with “P” rotating with layout data frame rotation changes is as designed. I’m recommending that this changes so user can specify angle rotation of a marker symbol in relation to the cartographic line (and keep Advanced ArcMap option to rotate unchecked).