If the engine is hot enough anything will burn (i.e. runners can eat whatever they want with no ill effects)
Taller runners have an advantage over shorter runners (most men's elite average slightly shorter than the norm, most women elite average slightly taller)
Don't worry about technique, your body will figure it out after many, many miles
The only way to get faster is to run high mileage
Anybody who beats an american at running has an unfair genetic advantage over americans.
Anything other than running will not help you run faster. Don't lift weights, stretch, do drills, or do ANYTHING other than run.