You start in D, when it hits redline shift down to 2, redline again then up to S3, redline again then S4. If you’re already driving around 2500rpm or like 60mph, you can throw it down to 2 for a noticable boost. It wont hurt your tranny too much, Honda trannies are some of the most durable trannies made. They are made for high rpms.
a bit off-topic but, how bad is it to engine brake with an AT? (shifting s4->s3->2)
its fine don’t worry about it
i just dont wanna blow something, as i’ve just discovered the fun of engine braking 
You’re just wasting fuel. But it’s good to practice a bit so you know how it works should your brake booster die on ya. I had to learn how QUICK! 
This is off topic, but what about launching an auto? What damage would it do to rev it up in Neutral, then just dropping it into 2, or D?
Ouch… I dont know how much but enough to make it not worth it, just powerbrake, probably works just as well.
Please explain how.
Well I am not overly familiar with the workings of a auto, since I have a manual, BUT I have a fair idea of how they work. Autos are kinda flakey as they are, in comparison to a manual tranny, meaning they they are more sensitive, to things like fluid, they have to have clean fluid or they die, and you cant take them as fast as you can a manual, at least no for an extended period of time, I have read a few stories in the ‘how fast can your car go’ threads about people topping out in autos, and then the auto just dying.
So I am just trying to imation what must happen when there is 80-90 ft/lbs of tourqe availble at the tourqe converter, when suddenly the tranny slamms itself into gear, auto trannys were in no way designed to be able to take this kind of abuse, so I doubt that they would put up with it for long.
I need a couple neutral drops before. Ended up shortening the life of my axles. Don’t do it.
But it didn’t fuck up your tranny?