Liquidity/Transaction cost in Sector Rotation Trades Fixed Income

From 2008 sample questions on CFAI: Sector rotation trading strategies do not perform well in the corporate bond market, as compared to the equity market, because the corporate bond market generally has less liquidity than the equity market and higher trading costs than the equity market. Is this still valid?, I can’t find anywhere in the text where it states this.

can’t think of any reasons why this is no longer correct! Corp Equity market is much more liquid than corp bond market and it has not changed, at least not in the US.

Same in China, the corporate bond market has much less investment targets and limited trading volume. while the equity market has become the second largest market.

Managed to stumble across it in the CFAI book too, its actially explained in Reading 44, page 12 in the quote driven market section.