I just read a comment on Mythic Haste. The guy says:
As far as buffing goes, Mythic Haste is, like haste, probably the best bang for you buck spell in existence. Giving your entire team +50 speed and an extra move action is INSANE. It's also amazing for yourself if you have a haversack full of scrolls, like any good Wizard should.
I am a bit irritated about the bold part. Does that mean that you can read a scroll with your additional standard action and get the scroll out of your backsack with the additional move action?
Just for more source:
The rules for Haste say that you cannot use the standard action for casting a spell.
The scroll rules say: Activating a scroll is a standard action. I am not sure if using a scroll is casting at all.