Throwing a closed form lidded jar

I am throwing an all in one lidded jar from a closed form. I think the most common struggle people have when throwing a closed form is not realizing how much clay needs to be left at the top of the as yet unclosed cylinder. When the walls are too thin before you begin to close it in, you will likely end up with a collapsed or wrinkled wall. Once you close the form, always remember to poke a hole in it somewhere unobtrusive to let the air escape as the clay shrinks. The “tool” I am using to create the lid flange is just one half of a clothes pin, and I slowly push it into the clay until I am relatively confident that the tool has pushed in at least the thickness of the wall so that the lid will fit. When ready to trim, I cut the lid away if the pin tool didn’t fully do the job when I threw it. Then I flip the lid upside down and use the body as a chuck. I will trim a bit on the lid and a bit on the body and will repeat until the fit is perfect. I will also usually trim the inside to thin the walls out at the bottom as little trimming on the outside will occur (except for the bottom of course).