Since this isn't posted yet:

(From the LOTRO wiki)

One mob pull: if facing one target mob surrounded by adds that are likely to assist, a cunning Lore-master can manage to fight just the one mob, and not any of the adds.

Start out by casting Blinding Flash on the mob from the maximum possible distance, then turn around and run. Once the adds have stopped pursuing you, return. After 30s have passed the mezzed mob will be free and will attack you -- but the adds will not follow.