The SuperTigre S2000 and G2300 are very different engines. There is a large difference in porting.

The S2000 was intended for sport use in larger models, with a mild fuel. The lower combustion pressures and power output were what contributed to the engine's lower oil requirement.

The G2300 was intended to be used in FAI pattern, but as a more economical answer than the O.S. or YS FAI engines. It's porting was developed to that end. That's also why it requires a regular 2-stroke glow fuel instead of the low-oil "ST" type fuel.