Databases are not self-healing animals, they require maintenance windows, period. I usually do weekly online re-indexing between 3-5AM on a Sunday morning, after the Sunday backups have taken place. In that way, I don't affect my U.S. systems adversely, even the 24/7 databases. For overseas databases i adjust accordingly.:-D
"Technology is a weird thing. It brings you great gifts with one hand, and it stabs you in the back with the other. ...:-D"