Just as the choice to put AD before or after is a style issue, the choice to use AD or CE is essentially a style issue since the two systems are numerically equ

Just as the choice to put AD before or after is a style issue, the choice to use AD or CE is essentially a style issue since the two systems are numerically equivalent. They probably feel that more of their readers prefer or understand AD than CE. (TRWTFs are the lack of a year zero and counting backwards sometimes and forwards other times.)