Ok,
On second thought, it doesn't seem to make sense at all that Expert Tactician would not apply during a total defense action. I understand that the clarifications unequivacally state that that is the case. However, think about it - it means that someone using Expertise would never EVER use the Total Defense option. Why would one take a total defense, a full round action, with no attacks, when he could get a higher AC while fighting defensively and using expertise, and have the option of attacking or moving?
Total defense - +4 AC (+6 w/5 ranks in Tumble)
Fighting Defensively w/Expertise - +2 to +7 (+3 to +8 w/5 ranks in Tumble). If you wanted to go for a Total Defense, you might as well fight defensively and go for the chance that you roll really high or in the case where you would never hit, score a natural 20. Even if you were using the total defense because you did not want to harm your opponent, it would still be more beneficial to fight defensively and hope to disarm, grapple, trip or hamper your opponent in some other way (again, perhaps w/a lucky roll).
IDHMBWM - as always seems to be the case when I make these posts, so perhaps I am missing something obvious, but if I am not I would houserule that you could use Expertise with Total Defense.