Cathie Wood is well known as the CEO of Ark Invest, an investment firm that focuses on owning businesses that have tremendous disruptive potential. Individual investors look to her for ideas, likely because the flagship Ark Innovation ETF is up 70% in 2023 (as of Dec. 22). On the list of holdings, you'll quickly see fintech powerhouse Block (SQ 0.31%). In fact, Ark Invest has made two sizable purchases of this company's stock just in the month of December. Should the average investor follow these moves? I t ...