I can see both sides of the argument and both have valid points. While I agree larger pistons/rings have more surface area to seal and should be babied to avoid potential damage, I believe hard beak in's to be more effective and I question any negative affect it would bring later on down the road.
Meaning, if a soft break in truly leads to blow by, low compression, smoking, who knows what other problems up front, you will most likely have those issues for the life of the engine. I doubt its ability to improve with time regardless if it was done "safely." On the same note, if a hard break in genuinely does create a more effective seal, thus eliminating the afore mentioned problems, albeit at the expense of scuffing/marring, I dont think you would see that seal deteriorate from prolonged use any faster than normal.