There is one minimal advantage to running a high ring pack. The closer you can shove a primary compression ring towards the top of the piston the smaller the amount of crevice volume. This nets an increase in compression and reduces a dead area in the combustion chamber. However for the most part this is for N/A motors since it is more prudent to keep a gasser or S/C motor's rings a little farther down so they are subjected to the more violent combustion events associated with chemical and mechanical super-charging.
OE components probably put the ring as high as possible (within the realm of durability) but have reached a point where they can no longer shove the ring pack up to reduce emmissions (thier primary concern) instead they are now reducing bore size to achieve the same effect. Hence the increase in strokes and the reduction in bore sizes.
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