You've all missed it. You're so hung up on thinking that carbs=energy you forgot that FAT is also an energy source. From my experience, a longer, slower burn than sugar preworkout. With carbs I'll hit a wall. However, an apple with an ample amount of natty PB? mmmmm....I'm going strong all workout.
Then spike it PWO, replenish glycogen IN the muscle.
But for PRE workout? Get some lipids in your blood already. Hey, I didn't think about cholesterol helping in the production of testoterone. Maybe some extra test helping as well?
Off topic: Filet is one of the fattier cuts. It's just marbled so you don't see a giant hunk of fat. Serious. Research it.