In the original Master Atlas, the elves did have the 2 hour meditation thing (SWMA 1st Edition, World Book p45: Races, Immortal Races, Elves).
The information disappears in the SWMA 2 and never comes back. Racial information in SWMA 2 changed significantly, and changed back in SWMA 3 but that part was not restored.
I don't know if it is intentional or simply something that was forgotten in SWMA2 and no one thought to include it again in the later atlases.