No matter which direction I'm shooting this shot, assuming this is the last ball and position isn't a concern, I don't like crossing the side-pockets. I want that cue-ball rebounding off that rail predictably and safely. If it's an uber-thin cut and I have to hammer it, I might use a little inside to create that perfect right-angle. If it's a long shot and not that thin, I might use a little bottom-outside to kill the speed.
As laid out by OP....it impossible to make the ball with center and scratch cross side, unless you overcut the shot or add inside English of even the smallest amounts. Rempe was a perfect example of proper mechanics on this type of shot. On extreme long cut shots of this nature I do everything I can to work the middle of whitey, unless its a two way free shot or something else. The contact point on the object ball is so Small with this type of shot, why would I introduce, any squirt when the natural shot being made, won't allow the side pocket scratch?