Huh?its like talking to a wall, they don't use that name anymore because blood elves is the name they use to honor the dead. A RENAME=/=A RACE CHANGE lol now yes the main difference between the elves from Quel Thelas and the ones in the alliance affiliated areas are that the Blood Elves had to resort to fel and stealing mana from creatures due to their mana addiction from the sunwell. the other elves most likely relied on power sources from Dalaran itself.
High Elves = All Elves from Quel'Thelas
Blood Elves = All High Elves who stayed in the City and witnessed the carnage from WC3 basically, changed name to honor the dead
Void Elves = High Elves=Blood Elves who dabbled in void, got corrupted and banished from Quel'Thelas
Silver Covenant Elves = Also High Elves but they basically don't really associate with their home anymore