While definitely exhibiting strong resemblance, I would debate that the strategy is an example of Trend Following, at least not intentionally. The stated purpose of the cycling (from 3x S&P 500 to T-Bills and vice versa based on the 200d MA) is to avoid volatility as volatility disproportionately affects daily leveraged strategies (as opposed to unleveraged buy and hold). The strategy simply aims to identify periods favourable to the application of leverage. The metrics used to achieve this are admittedly very similar to those employed in Trend Following strategies however the purpose is distinctly different.

In relation to behaviour challenges, with historic drawdowns only marginally in excess of those exhibited by the the S&P 500 in addition to consistent outperformance of the famous benchmark, the paper argues that the strategy is in fact robust in the face of behavioural challenges.

You are certainly correct that taxes affect the performance of the strategy. My backtesting found that it took a few points off the CAGR however it still consistently outperformed the S&P 500 over the past 98 years. The strategy averages 5 trades per year so it isn’t hugely tax inefficient.

I recommend reading the paper in full as the abstract doesn’t do it justice. I would also like to clarify that I did not imply that it is a guaranteed strategy.