How does this fictitious gain tax interact with the non-fictitious capital gains tax? In other words, if I were a rich man, and invested my assets gaining 5% as opposed to keeping them in a Scrooge McDuck vault, would I be taxed at 30% of fictitious 6% + 30% of real 5% i.e. effectively at 66% of my capital gains, or only at the "fictitious" income, or only at the real capital gains?