Often times professionals do what is practical for the size of equipment they use. Over the years, I've found that we as homebrewers adopt many methods used by professionals, because they are used by professionals, not because they are best for homebrewers. Also, just because a domed false bottom is not more efficient, does not mean it's less efficient. It also allows for more malt in the tun. I've done 3 batches with this system (Induction powered RIMS assisted BiaB). The first 2 were with bags, and the most recent was with a stainless 400 micron custom basket. I did not notice a significant difference in efficiency when I added the basket. Mash efficiency was about 67% on both the 2nd and 3rd batch. I've not been able to test it with a domed false bottom.