I am making some tweaks to yeast harvesting. In order to increase yeast reproduction and increase pitching rate, would you recommend setup a yeast starter and oxygenating it for > 24 hours using an aquarium pump with an in-line 0.2 microns filter? Would this setup maximize yeast reproduction and pitching rate? In other word, more oxygen, more reproduction? (This is obviously limited by the amount of sugar, yet this is not the point).
I'm not sure what your goal is here. It absolutely is NOT true that pitching more yeast is better. You just want to grow enough yeast to get to the optimal pitching rates for your OG. If you brew normal strength beers, a simple starter and a vial of yeast works perfectly fine. If you brew a lot of really high OG beers, you'll either need to make really big starters, reuse a chunk of yeast cake from a prior brew, or invest in stir plates etc to maximize yeast growth in a smaller volume.
I use the aquarium pump with an in-line 0.2 microns filter to oxygenate the wort (for the starter) before adding the yeast. What I have read is that, at the extend that the yeast detects oxygen, it will keep in aerobic mode and thus growing.
I use this set up since I harvest my yeast and I wanna maximize growth every time I make a starter.