Extra hero at the start of a bg

At the start of a bg eliminates the sated/unstuck in time etc debuff you get from casting
heroism/time warp/blood lust is eliminated. If you cast the spell within a second of the
start you get 40 seconds worth of the spell with no debuff.

You can't cast two of these spells in a row your self due to your personal cooldown on the spell,
but if someone else casts the same or similar spell you can benefit from the one after the other.

How useful this is depends on the bg. It is completely useless in alterac valley for example, but can be quite decisive at the start of say, silvershard mines where the starting areas are virtually
on top of each other. Rocket boots/speed buffs help obviously.