[voltron1011]

I just did this today and it was exactly as described.
I ended up connecting jumper cables to my Rav4, since I did the venting twice.
Also, I did not disconnect any hoses from the engine for draining. I just used an old motorcycle technique of blowing all of the coolant from the engine. I did this by attaching a rubber hose to the reservoir opening and filling in the gap with some plastic wrap so that the hose is perfectly sealed . Once this was done, I just blew the other end as hard as my lungs could muster, and most of the remaining coolant was blown out of the drain hole.
I ended up getting about 95% of the old coolant evacuated by this method.
Finally, I refilled the reservoir and did the venting process twice.
BTW, as others mentioned, the actual venting process isn't particularly loud, but it does sound like a washing machine going through it's cycles. I got under the car during the venting process and put my ear next to the water pump so that I could hear it cycling. And, yes it's exactly 12 minutes from start to finish.