Years of experience with these things shows that it really doesn't matter. They're not actually "rollers" - they slide to and fro without rolling. That's why some are actually asymmetric in shape and they're called "sliders". Or even "sliding rollers"! Performance may vary slightly, but you can always try them a different way. I grease the roller/sliders with a touch of lithium grease. Feel free to experiment.
Agreed to roller points, no difference how you put it.
For greasing: made the experience (in dusty ambiance) roller which were lightly greased had more wear due to collected muck.
I would only greasy the ones which are covered by a plate (some models) or according to factory standarts.
Saw, when CVTs innert ramps were nicely polished, less wear on ramps and rollers.
