which is closer to the center of the valve stem
But - that's not a function of geometry, only of the physical dimensions of the parts. Geo is far more important than having the rocker centered (which is entirely a safety and wear concern, not breathing or power), as long as it doesn't run close to the edge at any point.
The long pushrod reduces the side-thrust and wasted motion somewhat, but has no effect on the geometry (the triangle formed by the tappet cup, and inner and outer adjuster positions is too small to do anything). The geo on the short side is only less critical because there is no "scrub"; a geo error here (which you will get with a HS rocker adjusted to produce mid-lift on the long side) will reduce valve area in the same way.
What I have not figured out (and not ever) is:
1. how to determine what geo the manufacturer is shooting for (discarding their advertising)
2. what adjustment provides the best balance of curtain/area on both sides of the fulcrum.
