I have always rolled all mainsails, Pentex or otherwise, from the top down for storage. I was told to do this many, many years ago (more than I care to remember ) by a fellow catsailor who was also a sailmaker. If I remember correctly, this was to protect the majority of the sail, especially the exposed bolt rope and leech (if the sail was furled the other way), from damage. I don't recall anything about the bolt rope in particular though.

Prior to hoisting, I always unroll the sail completely and quickly check the battens/pockets/stitching anyway. If it's blowing at all much, I'll reroll the main from the bottom before hoisting it so that it can't be caught by the wind.

Each to his own I suppose.........