I don't agree with the things you’re saying now. You cannot use the continuous for the following reason: The present continuous implies something happening during a shorter period of time, which includes now, and wasn't happening before the period began or won't be happening when the period is over. Ex: I am doing my homework. This implies the following: A short while ago I wasn't doing my homework. In an hour or so I won't be doing my homework. Think about this for a minute and you will see the "I am agreeing" just doesn't make sense!

Great explanation!