Tax Strategies and Capital Gains

John is a high-net-worth individual considering the tax implications of his investment strategy. He currently holds a diverse portfolio that includes both taxable and tax-advantaged accounts. John is particularly interested in understanding how capital gains tax may affect his investment decisions.

During a review with his financial advisor, they discuss the importance of managing investments in a tax-efficient manner, especially considering his potential capital gains. The advisor recommends strategies to minimize tax liabilities while maximizing investment returns.

Which of the following strategies would be the least effective in minimizing John's capital gains tax burden?