I am really not sure how to make that distinction. It seems to me that to prevent "wealth turning into power" we would need essentially complete transparency on spending of the wealthy.

Also, I would probably much rather nail some risk (by limiting personal wealth to some reasonable amount) than risk "a leak" between wealth and power. Most founders, it seems to me, don't start overly wealthy; they would probably still risk starting their own business even if the "supergains" had zero probability (as opposed to really small probability).

Coupled with a good social and liability system (that will allow you reasonable life in case of business failure), financed from taxing of too much wealth, this can even increase the risk people are willing to take.