SUGGESTION: Bard is probably too strong on live now, with 2 songs and root. However, making their songs un-interrupt-able seems fine.
RATIONALE: At the start of combat a bard must perform 2 tasks simultaneously: change from speed to endurance song & mezz opponents. Bards cannot cast while attempting to sing a song. Even if everything goes perfectly, and no opponent interrupts your song transition, you must now demezz, cure disease and heal. Bards are forced to use MOC 1 when Endurance is interrupted.
Forcing a class to dump 5 Realm Points into an RA, to accomplish what Shamans and Paladins can do without interruption seems unbalanced.